The experience that turned many Union soldiers into abolitionists was the direct encounter with slavery during the Civil War. Here's why: - Witnessing the Brutality: Soldiers witnessed firsthand the horrors of slavery, including the physical abuse, forced labor, and separation of families. This firsthand exposure to the reality of slavery shattered many soldiers' previous assumptions and beliefs.- Interacting with Enslaved People: Union soldiers interacted with enslaved people, hearing their stories of suffering and their hopes for freedom. These personal connections fostered empathy and understanding.- Fighting for a Cause: Many soldiers initially joined the Union Army to preserve the nation, but as they experienced the realities of slavery, they began to see the war as a fight for freedom and equality. This shift in perspective led many to embrace abolitionism. The experience of the Civil War was a powerful catalyst for change, transforming many Union soldiers from individuals who may have been indifferent to slavery to passionate advocates for its end.