Ask HISTORY: What does it mean to cross the Rubicon? (3) tv-14 Play video Select your TV provider to log in to have full access to videos Select your TV provider See all providers Don't see your TV provider? Learn more You can access this video on the free HISTORY® app. *You must verify your TV provider towatch this video on the App Your Parental Control settings do not allow you to view this content. Ask HISTORY: What does it mean to cross the Rubicon? (3 min) tv-14 What does this expression really mean, and where does it come from? Get the answer now.