On May 4 (16 new style), P.L. Chebyshev was born - a great Russian scientist who represents the pride and glory of our Fatherland. In connection with the 200th anniversary of P.L. Chebyshev, a retrospective look at his contemporary era is offered and an attempt is made to comprehend the role of a genius personality not only in the history of science and technology, but also in the history of Russia, which he served with all his talents, including scientific and pedagogical. The report provides information about the tradition of serving the Fatherland in the Chebyshev family. A brief overview of the work of P.L. Chebyshev for 48 years at the Imperial St. Petersburg Academy of Sciences is presented. The memoirs of contemporaries about the work of P.L. Chebyshev for 35 years at the Imperial St. Petersburg University are discussed. The work of P.L. Chebyshev for 40 years in the Artillery Department of the Military Scientific Committee is considered. The work of P.L. Chebyshev for 17 years in the Scientific Committee of the Ministry of Public Education is analyzed. Its role in the educational reform (1863-1864) initiated by Emperor Alexander II is clarified, in particular in the development of the general university charter of 1863, in the compilation of recommendatory bibliography, in the organization of teaching mathematics in primary schools in Russia, in the systematic training of engineers in Russia. The role of P.L. Chebyshev in the creation of the Russian mathematical school is briefly highlighted.