Baseball was played during the Civil War mostly by Yankees but occasionally by Confederates.

Entity and relation annotations:
id: 0
type: entity
value: text: during the Civil War
labels: <Date>
id: 1
type: entity
value: text: the Civil War
labels: <Event>
id: 2
type: entity
value: text: Confederates
labels: <Organization>
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type: entity
value: text: Yankees
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labels: Event:Occurs_on:Date
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