When a natural disaster, pandemic, war or other crisis strikes, Americans have reacted with acts of kindness, turning both regular civilians and notables into heroes.

According to Rebecca Solnit, author of A Paradise Built in Hell: The Extraordinary Communities that Arise in Disaster, the great majority of people remain calm, resourceful and altruistic when helping others in times of crisis. "We improvise the conditions of survival beautifully,” she told Time magazine. “People rescue each other. They build shelters and community kitchens and ways to deal with lost children and eventually rebuild one way or another."

Here are 12 examples of small acts of kindness that made a big difference during the most difficult of times.

American Civil War

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President Abraham Lincoln with General George B. McClellan at his headquarters at Antietam during the Civil War on October 3, 1862. 

Toward the end of the four-year American Civil War, President Abraham Lincoln spent time visiting wounded soldiers at Depot Field Hospital along the Richmond-Petersburg, Virginia front, shaking hands with nearly everyone there, Noah Andre Trudeau writes in Lincoln's Greatest Journey: Sixteen Days that Changed a Presidency. In one tent, according to Trudeau, was Harry L. Benbow, a Confederate officer captured at Five Forks. As Lincoln extended his hand, Benbow told him he was offering it to "a Confederate colonel, who has fought you as hard as he could for four years." "'Well,' said (Lincoln), 'I hope a Confederate colonel will not refuse me his hand.' 'No sir,' I replied, 'I will not,' and I clasped his hand in both mine."

READ MORE: Abraham Lincoln

Smallpox Outbreak

The nationwide smallpox epidemic killed between 4,000 and 5,600 Americans from 1897 to 1903. In 1901, according to the Times Reporter in New Philadelphia, Ohio, it hit the Robinson family in Mineral City, Ohio. The parents, six kids and their belongings were quarantined in a farmhouse outside of town for months, during which time four of the children died.

“Their physician, Dr. William Willigman of Mineral City, also was placed in quarantine, living in a tent outside the house while attending to their daily medical needs,” the newspaper reports. While the surviving family eventually recovered, and Willigman was able to return home, as a precaution, all the family’s possessions, including their clothing, were burned. Released from quarantine, the Robinsons moved into a home owned by the Tuscarawas Coal and Iron Co.

“A complete new outfit of household furniture and utensils was given them by the Board of Health, and a generous supply of clothing was donated by the people of the community,” the Mineral Pointer newspaper reported at the time.

READ MORE: How an African Slave in Boston Helped Save Generations from Smallpox

San Francisco Earthquake of 1906

1906 San Francisco Earthquake
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The ruins of San Francisco, still smoldering after the 1906 earthquake and the three-day fire that followed it.

Following the disastrous earthquake and subsequent fires that left 3,000 people dead and half of the city’s residents homeless, a woman named Anna Amelia Holshouser was forced to camp out with a friend, eventually setting up at Golden Gate Park, according to Solnit’s A Paradise Built in Hell. There, Solnit writes, Holshouser made a makeshift tent out of fabric scraps that provided shelter for 22 people, many of whom were children, and started a tiny soup kitchen that soon grew to feed 200-300 people daily.

The Spanish Flu of 1918

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Red Cross volunteers fighting against the 1918 flu pandemic.

With a third of the world’s population infected in the 1918 pandemic, 50 to 100 million people, including some 675,000 Americans, died. Philadelphia was one of the worst-hit U.S. cities in terms of death rates, with all beds in the city’s 31 hospitals filled, according to the University of Pennsylvania School of Nursing.

Nurses from the Visiting Nurse Society of Philadelphia made home visits, handling a whopping 20-30 cases a day, many of which were families. “… In a crib beside the mother’s bed was a six-week-old baby who had not been bathed for four days and was wet and cold,” an annual report from the society read. “... The family had no coal, and the three well children were shivering and hungry. The nurse gave care to the sick and bathed and fed the baby. She made a wood fire in the stove and prepared food for the other children. She then found a kind neighbor to continue to look after the children.”

Johnstown Flood of 1889

The Johnstown Flood
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<em>The people of Johnstown inspect the remaining walls of the town's Catholic church, after the flood of 1899. More than 2,000 people died in the disaster.</em>

When heavy rain caused a dam to break in Johnstown, Pennsylvania, a 70-foot-high wave destroyed everything in its path over 14 miles. In the end, 2,200 people—one in 10 of the town’s population—died. According to the Johnstown Area Heritage Association, the flood was the American Red Cross’s first major peacetime relief effort, and Americans across the country and world were quick to respond.

“In Paris, Buffalo Bill Cody gave a benefit for the flood fund on June 13,” the association notes. “Charity also included food and goods of every kind: Cincinnati sent 20,000 pounds of ham and prisoners of Western Penitentiary in Pittsburgh baked 1,000 loaves of bread a day. The Standard Oil Company shipped a carload of kerosene to Johnstown. This vast stream of goods continued for months. When an accounting was attempted, it was estimated that 1,408 full carloads of goods, weighing 17,000,000 pounds, had been sent to Johnstown.”

READ MORE: How America's Most Powerful Men Caused America’s Deadliest Flood

Galveston, Texas Hurricane of 1900

Considered the worst hurricane in U.S. history, the Category 4 Galveston Hurricane of 1900 storm killed up to 12,000 people—one in six residents—destroying 3,600 homes and nearly decimating the entire town, which, at the time, was the most advanced city in the state.

One hero who emerged during the storm was Mother Mary Joseph Dallmer. According to the Texas State Historical Association, the Ursuline Sisters nun, elected superior in 1891, opened the doors of the Ursuline Academy to more than 1,000 refugees, “black and white, to calm their terror and meet their needs.” The nuns, who risked their lives to save people from the floods, were ordered by Mother Mary Joseph “to strip the convent of linens and give up their own wardrobes to clothe the refugees, and to share what food was spared by the tidal wave,” the association states.

The Houston Post, in a story reprinted nationally, wrote at the time: "A fearful catastrophe like that of September 8 brings out all that there is in a human being...and when all the noblest attributes...are brought out in one individual, and that a woman, mere words become too weak...to do her proper honor. Such a woman is Mother Mary Joseph. She is the heroine of the storm."

World War II

Battle of the Bulge
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Soldiers receiving food during the Battle of the Bulge, 1945.

Even in times of war, “the enemy” can surprise you. The Des Moines Register reports that Iowan Elmer "Curly" Richardson, drafted by the U.S. Army in 1944, and assigned to the 12th Infantry 4th Division, was a sergeant leading his troops at the Battle of the Bulge in the Hurtgen Forest on the Belgium-Germany border when his Jeep was ambushed by Germans and he was shot in the stomach and eventually captured.

"Elmer ended up on the operating table of a German doctor named Ludwig Gruber,” the newspaper writes. “Elmer should have died. He was an enemy combatant and not entitled to the same care and comfort as a wounded German, or at least that is what the hospital's commanding officers told Ludwig. Ludwig ignored them.”

While healing under Gruber’s care, a U.S. Army captain arrived under a truce. According to the Register, the captain met with Richardson and negotiated with the Germans, agreeing that the Americans would stop a planned bombing of the area if the Germans would stop parking their military vehicles there.

“How many lives were saved because Dr. Gruber had my father stay an extra week?” Steve Richardson, Elmer’s son, told the Register. “We’ll never know.” The men continued to correspond after the war.

The 9/11 Attacks

James Audiffred, an elevator operator at the World Trade Center who died during the 9/11 attacks, had loved the lighthouses of Maine, spending his last five summer vacations with his wife, Robin, in the Pine Tree state, according to The New York Times. After reading about Audiffred online and wanting to donate to an unsung victim, Carolyn and Gary Brouillard, owners of Dennett's Wharf in Castine, Maine, decided to donate the dollar bills they had been taping to the ceiling of their lobster restaurant for 11 years to the Brooklyn man's family. Robin Audiffred received a check for $12,313 from the Brouillards.

"They had no idea that Mr. Audiffred was in love with Maine lighthouses—not to mention Maine lobsters," the newspaper reports. "A total surprise," Gary Brouillard told the Times. "A total surprise."

Hurricane Katrina, 2005

When Hurricane Katrina ripped through New Orleans and the eastern Gulf Coast, killing 1,800, hundreds of volunteers, later dubbed the Louisiana Cajun Navy, rallied to rescue more than 10,000 people stranded and trapped by the floodwaters.

"They announced, 'Anybody wants to go help the people of New Orleans please come to the Acadiana Mall,'" Louisiana journalist Trent Angers told CBS News. "They expected 24, 25 boats. Between 350 and 400 boats and people showed up."

Told by authorities to stay away, the boaters were defiant. "You saw people in New Orleans walking in chest-deep water with all of their possessions floating in a plastic garbage can, and you're looking at it and thinking this is in our country, and in our case, it's two hours down the road," volunteer David Spizale told the network. "So we were hard-pressed not to go into action. That's where we wanted to be."

Hurricane Harvey, 2017

In the wake of Hurricane Harvey, Nick Sheridan, along with two other truck drivers, drove their tractor trailers some 200 miles and rescued more than 1,000 people, according to ABC News. “My whole life I’ve kind of been in that civil service role, but being on my own gave me the ability to go where they needed me rather than be stationed to go direct traffic on a street corner or something like that,” the veteran told ABC’s "Good Morning America." “I was really able to put my equipment to use here being a freelance rescuer.” Sheridan also posted on his Facebook page that the trio rescued 50 dogs—he adopted two of them.

Hurricane Maria, 2017

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Volunteer doctors organize medical supplies during a visit to a shelter to check refugees in the aftermath of Hurricane Maria in Humacao, Puerto Rico on October 2, 2017.&nbsp;

More than 3,000 people died as a result of the Category 5 hurricane that tore through the U.S. territory Puerto Rico, the U.S. Virgin Islands and Dominica, causing $90 billion in damages just in Puerto Rico. But, the New York Times reported, “small kindnesses came daily.”

From neighbors delivering bottles of water, ice and lanterns to providing child care to teachers traversing washed-out roads to visit students. “In Humacao, a municipality on the eastern shore where Hurricane Maria snapped sturdy trees in half like pretzel rods and flooded entire neighborhoods, teachers showed up at school the next day, unbidden,” the newspaper reported. “Fallen trees covered the courtyard. Mud caked the hallways and classrooms. They put on gloves and started to haul away branches. Eventually, cafeteria workers served up thousands of meals for the homebound and others in Humacao.”

COVID-19 Outbreak

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Jose Lanber cleans trash cans in North Station near an entrance to TD Garden and a photo of Celtics star Gordon Hayward in Boston on March 12, 2020. The NBA suspended the season in the wake of the spread of coronavirus.

When the NBA season was suspended due to the pandemic, players and owners announced they would financially help workers who would lose income during the break. Giannis Antetokounmpo and Khris Middleton of the Milwaukee Bucks each pledged $100,000 for arena staff.

“It’s bigger than basketball!” Anteokounmpo tweeted. Zion Williamson of the New Orleans Pelicans vowed on Instagram to pay Smoothie King Center staff for 30 days. Detroit Piston Blake Griffin and Cleveland Cavalier Kevin Love both pledged $100,000 to employees at their home arenas, while owners, coaches and players of the Golden State Warriors pledged to donate $1 million to a disaster relief fund. Rudy Gobert of the Utah Jazz, who was the NBA’s first player diagnosed with COVID-19, announced he was donating $500,000 to the cause, including $200,000 to go to Vivint Smart Home Arena part-time employees.