Jonas Vaidutis

Jonas Vaidutis (; ; 1365 – spring 1402) was a Lithuanian duke, priest, and academic rector from the Gediminid dynasty. Vaidutis was a son of duke Butautas and a grandson of the former Lithuanian monarch Kęstutis. Lithuanian-American historian Vanda Sruogienė deemed him the earliest known Lithuanian to graduate from a university. His pre-Christian Lithuanian name Vaidutis is sometimes confused with that of his uncle Vaidotas. By departing abroad Butautas left his recently born son Vaidutis in the Grand Duchy of Lithuania. It is thought that Vaidutis entered into the custody of his grandfather Kęstutis or possibly his uncle Vaidotas.

In 1381, around the outbreak of the first Lithuanian civil war, sixteen-year-old Vaidutis followed in his father's footsteps by departing to Prussia. He subsequently traveled to the imperial court in Prague, Jonas Vaidutis' career developed with the patronage of Władysław II Jagiełło. The election took place on St. Gall's Day, 16 October 1401. His candidacy was supported by the outgoing rector, Stanisław of Skarbimierz, who delivered a laudation in favor of the prince, emphasizing his theological education, noble birth, and virtuous conduct. He also mentioned that the prince had been a benefactor of the university.

Vaidutis did not hold the position of rector for long; by May of the following year, he was already deceased. During his tenure, the university admitted only 43 students. He was presumably buried in the Kraków Cathedral. His successor was , a canon of the Kraków Cathedral and later the bishop of Vilnius.