The Hapsburgs (or Habsburgs) were a relatively unknown family of Swiss Counts when one of their members, Rudolf, was named Holy Roman Emperor by the electors in 1273. The electors didn't want another strong ruler who they thought would only march off to war again and/or make the title hereditary - and they wanted someone they could control. So, they passed over the obvious choice, King Ottokar of Bohemia, and chose the relatively unknown Count Rudolf of Hapsburg.
At the time he was notified of his selection, Rudolf was laying siege to the Bishop of Basel. At first he thought the young emissary was joking, but once convinced, he released all his prisoners, lifted the siege, and set out for Aachen.
The Bishop of Basel, who knew Rudolf better than anyone, realized the electors had severely underestimated their choice was said to have muttered, "Now sit tight, Lord God, or Rudolf will have your throne!"
Unfortunately the title of Holy Roman Emperor passed out of the hands of the Hapsburgs with the death of Rudolf's son, Albrecht, and it would be nearly 150 years before they got it back. When they did, though, they held on to it until the Empire itself was dissolved in 1806.
Now, on to today's question. In 1438 Albrecht II became Holy Roman Emperor. He was Rudolf's great-great-great-grandson. Because he only left daughters, a cousin, also Rudolf's great-great-great-grandson, Frederick (III), became the next Holy Roman Emperor.
Frederick III did very little right during his reign, but the one thing he did established the House of Hapsburg and staked it's place in history. He married his son and heir to Mary of Burgundy - the only child of Charles the Bold.This Day in History: Charles the Bold of Burgundy is killed during the Battle of Nancy on this day in what year?