Robert S. Horowitz, founding editor of the Montgomery Journal newspaper in Rockville, died Feb. 1 at a nursing home in Kensington, Md. He was 89.

He had Alzheimer’s disease, said his daughter Ellen Stein.

Mr. Horowitz, a Bethesda resident, began his career as the night editor of the Transradio Press Service’s Washington bureau from 1948 to 1951. He then became a staff editor and columnist for the Navy Times until 1963.

He then covered Congress for the Army Times newspaper group from 1963 to 1973, serving as chairman of the House and Senate Periodical Press Galleries, an organization of congressional correspondents, in 1972.

A year later, Mr. Horowitz became the first editor of the Montgomery Journal, which was published by the Army Times Publishing Co. and focused on issues of importance to Montgomery County, Md. He increased the publication schedule from one day to five days a week and circulation reached 50,000, his family said, before his retirement in 1986. The newspaper ceased publication in 2005.

Robert Sidney Horowitz, a native of Baltimore, served in the Army in the European theater during World War II and received the Bronze Star Medal and Purple Heart.

He attended George Washington University and other colleges and was the co-author of two books about the military in the 1960s.

Mr. Horowitz served as president of the International Society of Weekly Newspaper Editors in 1977. He was a docent at the Corcoran Gallery of Art from 1986 to 2006.

Survivors include his wife of 65 years, the former Sandra Bergstein, of Bethesda; three children, Ellen Stein of Philadelphia, Carol Fuchs of Bethesda and Charles Horowitz of Bloomington, Ind.; and eight grandchildren.

— Samantha Raphelson