Walker was captured at the Battle of Wilson’s Creek on August 10, 1861, and he spent a year as a prisoner of war. In August 1862, he signed an oath promising not to take arms against the U.S. government and then joined his family in Corsicana, Texas, where he stayed for the remainder of the war. In the summer of 1865, the family returned to Fayetteville, where Walker resumed his law practice
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Upon the outbreak of the Civil War, Walker served as a colonel of the 4th Regiment, Arkansas State Troops; he was captured at Oak Hills, Missouri in 1861 and held as a prisoner of war for two years.
http://en.wikipedia.org/wiki/James_D._Walker

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For additional information:
Lemke, Walter J., ed. The Life and Letters of Judge David Walker of Fayetteville: Justice of the Arkansas Supreme Court, 1848–1878. Fayetteville, AR: Washington County Historical Society, 1957.

———. The Walker Family Letters. Fayetteville, AR: Washington County Historical Society, 1956.

Thompson, George H. Arkansas and Reconstruction: The Influence of Geography, Economics, and Personality. Port Washington, NY: Kennikat Press, 1976.
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