Matthew P. Gallagher Sr., 80, an author and retired Central Intelligence Agency branch chief specializing in Soviet military history and affairs, died of renal failure Nov. 26 at Inova Fairfax Hospital. He had lived in Falls Church since 1953.

Fluent in Russian and French, Dr. Gallagher worked at the CIA from 1953 to 1984 and retired as branch chief for Russian internal affairs at the agency's foreign broadcasting information services division.

Since August, he had worked as a consultant to Raytheon Co.

Besides numerous articles on Soviet military policy, some of which appeared in The Washington Post, he wrote "The Soviet History of World War II: Myths, Memories and Realities," published in 1963 by Praeger Publishers. With co-author Karl Spielman Jr., Dr. Gallagher wrote "Soviet Decisions--Making for Defense," published in 1972 by Praeger.

In the 1980s, he was a visiting fellow at the Center for Defense Information, a Washington think tank, and taught history at the Institute for Learning in Retirement, a continuing education program, at George Mason University and American University.

He was a former staff member of the Institute for Defense Analysis.

Dr. Gallagher was born in Providence and graduated from Providence College in 1937 with a bachelor's degree in history. At Harvard University, he received a master's degree in history in 1949 and a doctorate in Russian history in 1960.

He served in the Navy during World War II.

In the early 1950s, he taught history at two Massachusetts schools, Wheaton College and Newton College of the Sacred Heart.

He was a member of St. James Catholic Church in Falls Church.

Survivors include his wife of 56 years, Roberta M. Tierney Gallagher of Falls Church; two sons, Matthew P. Jr., of Annandale, and Robert C., of Falls Church; a daughter, Paula M. Moore of Jessup; a brother; two sisters; and two grandchildren.