Complex sentence: On his chest, Lean Bear wore with pride his peace medal that he had received on his trip to Washington D.C. in 1863, and in his hand held an official document, signed by President Abraham Lincoln, stating that he was peaceful and friendly with whites.
Split into simpler sentences: On his chest, Lean Bear proudly wore his peace medal that he had received on his trip to Washington D.C. in 1863. In his hand, he held an official document signed by President Lincoln stating that he was peaceful and friendly with whites.