How many years did Mendel serve as abbot of his monastery?

Mendel served as abbot of his monastery for 16 years.

Gregor Mendel was elected abbot of the Augustinian monastery in Brno in 1868, succeeding Cyrill Napp. He held the position until his death on January 6, 1884—roughly 16 years later. The usual historical summary therefore describes his tenure as 16 years, even though the dates do not represent sixteen complete calendar years.

Becoming abbot changed the course of Mendel’s scientific life. The position brought extensive administrative, financial, and religious responsibilities. He became involved in a prolonged dispute with the government over taxes imposed on monasteries, which consumed much of his time and energy.

Mendel continued some scientific interests, including meteorological observations and beekeeping, but his major pea-hybridization work had largely ended before or around his election. He had presented his famous findings in 1865 and published them in 1866. Recognition came much later, around 1900, when other scientists rediscovered the significance of his inheritance experiments.