Question

yorktown
who led the forces at
yorktown?

why did lord cornwallis
surrender?

Explanation:

For the first question: On the American side, George Washington led the combined Continental Army and French forces. On the British side, Lord Charles Cornwallis commanded the British troops at Yorktown.
For the second question: Lord Cornwallis surrendered because his British army was trapped in Yorktown by the combined American and French land forces, while the French navy blocked the Chesapeake Bay, cutting off his supply lines and any chance of escape or reinforcement.

Answer:

1. On the American/French allied side: George Washington; On the British side: Lord Charles Cornwallis
2. Cornwallis surrendered because his army was surrounded by allied land forces, and the French navy blocked his escape/supply routes, leaving him with no viable path to continue fighting.