Mary Layfield Nock was a politician who served in the Maryland State Legislature from 1947 through 1974. She was born on September 4, 1903, in Green Hill, Wicomico County, Maryland. At the age of four she and her family moved nearby to the town of Quantico. She later attended one of the branches of Beacom Business College (now Goldey-Beacom College) in Salisbury, Maryland. On April 11, 1925, she married Garland Nock, a Salisbury construction official.
After graduation, Nock's active involvement in politics began in the mid-1920s when she took over her Aunt Ola's job as secretary for David J. Ward, a Wicomico County businessman. Nock continued to work as Ward's secretary when he became a Maryland State Senator (1926 through 1934 and 1938 through 1939) and then U. S. Representative from Maryland (1939 through 1945) and traveled with him to work in Washington, D. C. and in Annapolis, Maryland for several days a week. According to Nock, she "went to Washington… every Monday morning…[and] return[ed] to Salisbury by bus on Wednesday evening to keep [Ward's] Salisbury office open on Thursday, Friday, and Saturday" (It was a Joy and a Pleasure, 13). After Ward lost his bid for re-election in 1944, Nock returned home to Wicomico County.
In 1946, she ran successfully for a seat in the Maryland House of Delegates. Nock was the first woman from Wicomico County to be elected to the Maryland General Assembly and remained in office until 1955. Then, from 1955 to 1974, she served in the Maryland Senate. During her tenure in the legislature, Nock interacted with several of Maryland's governors including William Preston Lane, Jr., Theodore R. McKeldin, J. Millard Tawes, Spiro T. Agnew, and Marvin Mandel. She was an advocate for women's issues, higher education, and the use of television as an educational tool. She served on various councils, committees, and commissions, including the Southern Regional Education Board, the Education Commission of the States, and the National Conference of Legislative Leaders. She was an honorary member of the Soroptimists International, the Maryland Congress of Parents and Teachers, the Delta Kappa Gamma Society, and many others. In 1979, Nock wrote and published It Was a Joy and a Pleasure, a narrative of her life experiences.
After sixty-two years of marriage, Mary Nock died on May 20, 1987, at the age of eighty-three. She and Garland did not have children.