Late bloomers

We've all read the stories about some master chess player who was taught the game at an early age. Seems to be the norm really.

I was curious though, are their any great examples of players who took up the game in their twenties or thirties or even later who then went on to notable success in chess?

Rubinstein and Staunton were reportedly 19 when they learned the game.

Albin was 23.

McDonnell was 25 (2nd best in the world in his time).

http://www.geocities.com/SiliconValley/Lab/7378/learn.htm

The oldest player to become a Chess Master was Oscar Shapiro, at age 74.

Akiba Kivelovic Rubinstein was born December 12, 1882 in the Polish border town of Stawiski.  He learned to play Chess at the age of 16 in school where he played his classmates...