A prominent and wealthy Hungarian aristocrat, son of Baron Miklós Wesselényi and Ilona Cserei, he was born at Zsibó (now Jibou), and was educated at his father's castle by Mózes Pataky in a liberal and patriotic direction.

Wesselényi entered politics in 1818, taking minor positions at numerous County Diets, as was customary with the upper nobility his family belonged to.

Wesselényi abolished several feudal laws and customs on his own estates, freed his serfs, built and ran schools on his own money, and organized lectures on modern agriculture for his former subjects.

He held several speeches on current topics attacking feudal institutions, and printed and distributed the minutes of the Diet in order to give publicity to the debates.

[3] For these activities, the government took him to trial for inciting unrest, operating a printing press without royal permission, and also for one of his speeches, where he called for general land-redemption.

After serving 2 months in the casemates of the Buda castle, he started to have a serious eye ailment, and he was permitted to travel to Gräfenberg (now Lázně Jeseník) in Silesia with his family in order to cure his illness.