Civil War Union Army Surgeon. He was mustered in as an Assistant Surgeon in the 35th Ohio Volunteer Infantry on November 13, 1862. He was severely wounded at the June 1864 Battle of Kennesaw Mountain, Georgia, and was honorably mustered out on September 27, 1864.

On September 1, 1865 he filed for a US Army Invalid Veteran Pension (Application #86177, Certificate #74507).

"Case 693. — Assistant Surgeon A. H. Landis, 35th Ohio, aged 39 years, was wounded near Kenesaw Mountain, June 22, 1864, by a twelve-pound solid shot, which, after hitting a tree and bounding off, struck his right leg, causing fracture but not breaking the skin. Surgeon F. D. Morris, of the regiment, reported that the missile fractured both bones of the limb midway between the knee and the ankle, and that the soft parts were much contused. The patient was admitted to the field hospital of the 3d division, Fourteenth Corps, where he received a leave of absence on the following day. He was mustered out of service September 27, 1864, and pensioned. Examining Surgeon J. S. McNeeley, of Hamilton, Ohio, certified, October 31, 1865: "The leg was struck at the posterior part of the middle third, fracturing both the tibia and fibula and lacerating the gastrocnemius and soleus muscles. The resulting cicatrices have formed adhesions to the adjacent parts, entirely destroying their action. In adjusting the fracture complete apposition was not attained, and, from extension of inflammation, there is partial anchylosis of both knee and ankle joints, rendering locomotion both painful and difficult," Subsequent examiners report no additional information. The pensioner was paid September 4, 1879." -- The Medical and Surgical History of the War of the Rebellion. Part III, Volume II. (3rd Surgical volume) by U.S. Army Surgeon General's Office.

On January 2, 1898 his wife, Mary Kumler Landis, filed for a US Army Widow's Pension (Application #645190, Certificate #445724).

He was the father of 1st Major League Baseball Commissioner Kennesaw Mountain Landis.

Obituary: Dr. A. H. Landis, of Logansport, Well-Known Army Surgeon. LOGANSPORT, Ind., Nov. 9 - Dr. A. H. Landis, of this city, died this afternoon at the advanced age of seventy-five. He was the father of Hon. Kenesaw M. Landis, of Chicago, private secretary of the late Secretary of State W. Q. Gresham during Cleveland's first administration, and also father of Congressman-elect C. B. Landis, of the Ninth Indiana district. Deceased was one of the most respected citizens of this city. He served through the war as surgeon of the Thirty-fifth Ohio Volunteer Infantry and was severely wounded at Kenesaw mountain. He has contributed valuable information in the shape of historical reference to battles in which he participated and was widely known through his war writings. W. K. Landis, formerly an Indianapolis newspaper man, now of the Marion Chronicle, together with Fred Landis, a young attorney of this city, are sons of the deceased. [Indiana State Journal (Indianapolis, Indiana), Wednesday, November 11, 1896, pg. 5]