I apologize for the mistake in my response. Upon reviewing the events, here is the correct chronological order:
1. Dred Scott court case (1857)
2. Georgia secedes from the Union (1861)
3. Election of 1860
4. Civil War (1861-1865)
5. Founding of Freedmen's Bureau (1865)
6. Removal of black legislators in Georgia General Assembly during Reconstruction (1868)
This order aligns the events according to their dates, starting with the earliest event (Dred Scott court case) and ending with the latest event (Removal of black legislators in Georgia General Assembly during Reconstruction).