Who is Solomon Lefschetz from A Beautiful Mind: A Biography of John Forbes Nash, Jr., Winner of the Nobel Prize in Economics, 1994 and what is their importance?

Solomon Lefschetz is the mathematician who recruited Nash for graduate work at Princeton. He was chairman of the mathematics department there. He was born in Moscow and educated in France. He received his PhD in mathematics from Clark University, where he met and marries his wife. After teaching in Nebraska and Kansas, he accepted a position at Princeton.