Final answer:
General Lee's surrender occurred in April 1865, after a series of Confederate defeats and Union advances.
Step-by-step explanation:
The events leading up to General Lee's surrender can be traced back to April 1865 during the American Civil War.
Following a series of Confederate defeats and Union advances, General Lee and his Army of Northern Virginia found themselves surrounded and outnumbered by General Grant's forces.
Realizing the dire situation, General Lee decided to surrender on April 9, 1865, at Appomattox Court House in Virginia, effectively ending the Civil War.
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