LONDON, NOV. 26 -- Lord Duncan-Sandys, 79, a member of Sir Winston Churchill's World War II Cabinet and a commonwealth secretary in the early 1960s who assisted 11 former colonies in achieving independence from Great Britain, died at his home here today after a long illness. The cause of death was not reported.

As Mr. Duncan Sandys -- he was created a life peer in 1974 and took the title Baron Duncan-Sandys -- he had a political career that spanned more than three decades and took him to the highest reaches of government and the Conservative Party.

An early advocate of European unity in the postwar era, he was outspoken in backing various issues often associated with the right wing of his party. These included the death penalty and limiting immigration of nonwhites to Britain.

First elected to the House of Commons in 1935, Mr. Sandys (pronounced Sands) joined Winston Churchill, whose son-in-law he became in September of that year, in criticizing the appeasement policies of Conservative prime ministers Stanley Baldwin and Neville Chamberlain.

When war broke out in September 1939, Mr. Sandys was called to active duty as an officer in an antiaircraft unit. He later served in the ill-fated Norwegian campaign. Back in Britain and a lieutenant colonel, he was injured in an automobile accident.

For the rest of the war, he held a number of high government posts. In 1942, while at the War Office, he helped plan an air raid that was designed to destroy the German rocket development station at Peenemunde. In 1943 and 1944, he was parliamentary secretary for the Ministry of Supply. Because of his special knowledge of antiaircraft weapons he was made chairman of a Cabinet committee to devise defenses against the flying-bomb blitz that the Germans launched against London in June 1944.

The V-bomb attacks lasted for 80 days. To cope with the devastation, Mr. Sandys was made minister of works, a post that carried Cabinet rank and a seat on the Privy Council.

In the general elections in July 1945, the Labour Party won by a landslide and he lost his seat in the House of Commons. For the next five years he led a private life, but was active in the European Movement, one of the forerunners of the European Common Market.

In 1950, Mr. Sandys returned to the House of Commons. He was named minister of supply and then minister of housing and local government. From 1957 to 1959, he was minister of defense. He spent 1959 and 1960 as minister of aviation.

From 1960 to 1964, he was secretary of state for commonwealth relations and colonial secretary. It was in this position that he implemented Prime Minister Harold Macmillan's "wind of change" to dismantle the British Empire. During his tenure, 11 colonies gained independence: Jamaica, Trinidad and Tobago, Cyprus, Malta, Malaysia, Nigeria, Kenya, Uganda, Malawi, Tanganyika (now Tanzania) and Sierra Leone. All remained in the British Commonwealth, the 48-nation association of Britain and its former colonies.

In 1962 Mr. Sandys wrote, "Britain has no desire to hold on to her remaining colonies a day longer than is necessary. Politically they involve us in much unwelcome controversy with the outside world -- and economically, we draw no profit from our sovereignty."

The Labour Party returned to power in 1965. In subsequent years Mr. Sandys' influence declined as a new generation came to power. In 1974, he resigned from the House of Commons and was elevated to the peerage. He pursued business interests and became chairman of the Lonrho conglomerate in 1983.

Born Jan. 24, 1908, into a family of landed gentry, Duncan Edwin Sandys was educated at Eton and Oxford and joined the Foreign Office in 1930. A speaker of French, Russian and German, he was posted to Berlin. He quit the diplomatic service in 1933.

In 1960, he and the former Diana Churchill, by whom he had one son and two daughters, were divorced. In 1962, he married Marie Claire Schmitt. They had one daughter.

ANNE RUTHERFORD BENNETT,

70, a retired lawyer with the Interior Department's Bureau of Land Management, died of cardiac arrest Nov. 14 at the Winchester Medical Center in Winchester, Va. She had lived in Winchester since moving there from Falls Church in June.

Mrs. Bennett was a native of Harrisburg, Pa. She was a 1939 graduate of Goucher College and moved here about 1942. During World War II, she worked in code-breaking with the Army Signal Corps.

After the war, she worked for the American Export Airlines before receiving a law degree from George Washington University in 1951. She did volunteer legal work for women's groups and legal aid organizations before joining the Bureau of Land Management in the late 1960s. She retired about 1981.

Mrs. Bennett had been a volunteer for the American Red Cross and Fairfax Hospital.

Survivors include her husband, William B. Bennett of Winchester; a son, William B. Bennett Jr. of St. Louis, and a sister, Jeannette Pilchard of Salinas, Calif.

CYNTHIA C. CROCE,

58, a former free-lance writer who had worked for the Environmental Protection Agency, died of cancer Nov. 15 at a hospital in Denver, where she had lived since June of this year.

Mrs. Croce was born in Chicago. She graduated from the Art Institute of Chicago and attended the graduate school of the University of Maryland.

She moved to the Washington area in the early 1960s and had been a free-lance technical writer for various employers, including the EPA. She moved to Colorado five months ago.

Her marriage to Giovanni Croce ended in divorce.

Survivors include two sons, Matthew Croce of Denver and Christopher Croce of Lemoore, Calif.; her mother, Myra K. Chapman, and a sister, Deborah Chapman, both of Chicago, and a brother, Peter Chapman of San Antonio.