Tydings was born in Asheville, North Carolina, but attended the public schools of Aberdeen, Maryland. He was adopted as a child by Millard Tydings, who also was a Maryland Senator. He went on to graduate from McDonogh School in 1946, the University of Maryland, College Park in 1950, and the University of Maryland Law School in 1953.

During the Second World War, Tydings served as a corporal in the Sixth Constabulary Regiment of the European occupation army. After his service, he was admitted to the bar in 1952 and was elected to the Maryland House of Delegates in 1955. Tydings served as a delegate until 1961, at which time he was appointed the United States attorney for Maryland. In 1963, he served as the United States representative at the Interpol Conference in Helsinki, Finland, and at the International Penal Conference in Bellagio, Italy.

Tydings was elected as a Democrat to the United States Senate in 1964. While Senator, he was the chairman of the Committee on the District of Columbia in the Ninety-first Congress. Tydings failed to be re-elected in 1970 and was defeated by the Republican candidate, J. Glenn Beall, Jr. Tydings also lost the 1976 Democratic primary to fellow democrat and current senator Paul Sarbanes.

Tydings has since served on the Board of Regents of the University of Maryland from 1974-1984, serving as chairman 1982-1984 and as a member of Board of Regents of the University System of Maryland from 2000-2005. He is currently a senior counsel to the law firm of Dickstein, Shapiro, Morin and Oshinsky in Washington, D.C. and resides in Harford County, Maryland.

This article incorporates facts obtained from the public domain Biographical Directory of the United States Congress.