This assumption is confirmed by the fact that Stephen served as envoy of Charles to foreign lands at least nine times by 1326, which assumed he was fluent in French and Italian.
[3] Following the end of the Mongol invasion of Hungary, Béla IV donated the entire territory to his wife Maria Laskarina thus Požega County became a permanent queenly estate.
In 1281, Queen Dowager Elizabeth donated the villages Alsókamarica and Berzince to her courtly youths, brothers Ambrose and Leonard of Požega, respectively.
Stephen functioned as interpreter in that delegation, which was sent to Prague and Zbraslav led by Thomas Szécsényi and Simon Kacsics on 18–23 January 1318 in order to find a bride for Charles, whose previous (first or second) wife Maria of Bytom, had died in 1317.
According to the report, John of Bohemia called his two sisters to his court and the Bohemian king gave the envoys the opportunity to choose between them their future queen.
[5] After defeating the Borsa clan in Transtisia, Charles I waged war against another oligarch Matthew Csák and captured Komárom (now Komárno in Slovakia) and Visegrád in autumn 1317.
[6] In the next year the king expanded the estate with surrounding lands (e.g. Szentendre was received from Stephen Kéki, the Bishop of Veszprém in exchange for domains in Zala County).
[9] In the first half of 1323, Charles decided to move his capital from Temesvár (today Timișoara in Romania) to Visegrád, which laid in the centre of his kingdom.
After the death of Charles, Queen Mother Elizabeth confirmed his received land donations and granted privilege of tax exemption, including marturina which was traditionally collected in the then highly valued marten skins in Slavonia.
[11] Stephen also acquired estates in Bács and Torontál Counties, as well as in the surrounding countryside of Visegrád (including Diósd and Nyírmál).
On 15 September 1326, the childless Mikócsa Rosd, a former familiaris to Matthew Csák, adopted Stephen as his son and made him as his heir.
Gaining pardon later, Nicholas and John was able to recover a portion of their property but gradually impoverished and forced to mortgage their inherited estates.