Final answer:
The fall of Richmond and the surrender of Confederate General Robert E. Lee to Union General Ulysses S. Grant marked the end of the 9-month siege of Petersburg.
Step-by-step explanation:
The 9-month siege of Petersburg resulted in the fall of Richmond and the surrender of Confederate General Robert E. Lee to Union General Ulysses S. Grant. Lee evacuated Richmond on April 2, 1865, and Grant pursued him, leading to several clashes between their armies. On April 9, 1865, Lee surrendered to Grant at Appomattox Court House in Virginia, marking a significant event in the American Civil War.