On March 13, 1945, he was taken by the Soviet authorities, held in a camp in Tisza Kálmán - Republic Square, and then in Csömör until April 19, 1945.

Meanwhile, during one of his interrogations at the Mosonyi prison, he coincidentally met with his father, who had succumbed to his injuries due to abuse suffered in captivity two days before his release.

In November 1952, he was deported by the police to Keszthely, then to Veszprém, and to the Budapest provisional detention facility in early December.

His second wife, Margaret Hertelendy (Pacsa, Zala County, March 26, 1925 - Budapest, September 5, 2021) was a divorcée from Hertelend and Vindornyalak of ancient Transdanubian origin.

Margaret's maternal grandparents were Dezső Szentmihályi (1863–1935), a landowner, member of the Upper House and vice-president of the "Zalavármegyei Economic Association", and Ilona Koller (1871–1934).

Szécheny spent his childhood in Sárpentele, Fejér County (now Sárszentmihály), and in his Austrian and Czech relatives' homes in Gutenstein, Milleschau and Niemes.

He completed his higher education in Munich and Stuttgart between 1920 and 1921, and in 1922-1923 he further expanded his language and zoological knowledge in Oxford and Cambridge.

He suffered a lot of injustice in the Rákosi era, but then in the 1950s he entered the Keszthely Helikon Library, where he worked on a professional bibliography on hunting literature in four languages.

In 1960 he went on an official state expedition to East Africa (with István Dénes, János Szunyoghy, Imre Schuller and Kornél Böröczky).

His specialist library miraculously survived World War II, counting more than 4,000 volumes at the time of his death.

Between 1915 and 1930, he hunted red deer mainly in the Bakony, Vértes and Kőröshegy estates in Hungary and therefore traveled to the Carpathians.

During his travels in Europe, he visited several countries, including black grouse in Scotland, Alpine ibex in Italy, and so on.

October 2022, several personal items were added to the exhibition, including furniture, paintings that had been in the home of Margit Hertelendy through the decades.