Hero of the Rhine: Karl Heinrich Timmermann was the first American officer to cross the Rhine River in Germany during World War II.

 Hero of the Rhine: Karl Heinrich Timmermann was the first American officer to cross the Rhine River in Germany during World War II.

Karl Heinrich Timmermann (June 19, 1922 – October 21, 1951) was the first American officer to cross the Rhine River in Germany during World War II after directing the assault across the bridge, helping remove explosive charges, and surviving the German Army demolition attempt to destroy the Ludendorff Bridge at Remagen on March 7, 1945. 

Born in Frankfurt am Main, Germany on 19 June 1922, to German bride Marie Franciska (Weisbecker) and John Henry Timmermann. Karl and his parents came to the U.S. in 1924. 

The summer of 1939, with one more year left in high school, Karl joined the Citizens Military Training Corps at Fort Crook for thirty days of intense military training. He graduated from Guardian Angel High School, West Point, Nebraska, in 1940. 

Timmermann enlisted in Regular Army 6 July 1940, received basic training with Company "D", 17th Infantry at Fort Crook, Nebraska then on to Fort Ord, California.

 He was assigned to Fort Lewis, Washington, with Company D, 30th Infantry on 25 March 1941, and later to the Presidio of San Francisco. On 7 December 1941, Karl was serving in the Northwest Defense Command at Fort Lewis, Washington.

 On 26 April 1942, his entire unit was reassigned to the 81st (Wildcat) Division at Camp Rucker, Alabama. 

On 21 May 1942, Karl was stationed with the 323rd Infantry Regiment, Company D, at Camp Rucker. On 10 November 1942, Karl's application was accepted for Officer Candidate School.

 He attended Officer Candidate School at Fort Benning, Georgia from 18 November 1942 to 16 February 1943, and appointed 2nd Lt, Infantry, AUS on 16 February 1943.

 Assigned as a Platoon Leader in Headquarters Company, 2nd Battalion, 52nd Armored Infantry Regiment of the 9th Armored Division at Fort Riley, Kansas, late February 1943.

Promoted to 1st lieutenant, AUS, on 16 April 1945, and relieved from extended active duty on 12 December 1945. On 28 October 1947, Karl reenlisted in the regular army as a Tech/Sergeant, officer billets were full.

 Recruiting in Nebraska and Iowa until December 1947, Promoted to Sergeant First Class August 1948, on which date he was assigned to the 5258 ASU, Nebraska State Senior Instructor, OR serving until December 1948. On 26 December 1948, he was sworn in as a 1st Lieutenant.