János Kemény was born in 1903 in Pittsburgh U.S. state of Pennsylvania. After the death of his father, his mother - a beautiful actress Ida Mitchel - was left alone with 4 children. Unable to secure the living for herself and the children, in December 1904 emigrates to her husband's relatives in Transylvania. János and his family arrives to his paternal grandfather Ödön Kemény who lived in Alsójárára.
”I do not remember my father, I simply take in consideration that he existed, and I also note that he went through many ordeals. I sincerely was sorry for him, I’ve heard how many injustice happened with him. I knew that he did not deserve his harsh fate.” wrote János Kemény in his autobiography.

János's father, István Kemény

What happened, was that a military commander, István’s superior, a wealthy prince, asked him to sign a bill. István knowing that the prince is very rich, signed it without thinking, but the prince disappeared, so István had to pay back the bill. The desperate young hussar lieutenant, who was also a teacher at the Vienna riding school, asked help from his rich relatives from Marosvécs/Transylvania. Kálmán, his uncle, the owner of the Marosvécs castle, was willingness to pay, but his wife, aunt Pólika (Bánffy Polixéna) stipulated conditions: They pay the necessary amount, but István has to emigrate to America. So became out of János’s father an exiled, a New York dock worker, a dish-washer,  a hotel elevator-operator and later a clerk.
 The house in Alsójára became intermittently for more or less thirteen years the home of the settled family. János loved this reagion, he has spent here his most beautiful days of his life. Writes about himself: “I gained consciousness here in Alsójára and my beautiful childhood memories are attached to this village. Therefore, I consider - instead of Pittsburgh – my hometown Alsójára and my homecountry Transylvania.”
When János was 10 he went to the Reformed College in Kolozsvár. After his baccalaureate in the autumn of 1921 he was enrolled in the University of Wienna Hochschule für Bodenkultur forest engineering.

While being at the university, one day the "miracle" has come in János’s life:

According to the will of his uncle Kalman and his aunt Pólika néni, having no children , irrevocably had designated him heir to the Marosvécs castle and property. Thus, the son of the exiled István, János Kemény became the heir of the same Marosvécs castle which was first owned by the Prince of Transylvania with the same name.
The young baron became the landlord of the Marosvécs manor in 1923. With this new situation a new chapter begins in his life.

After János inherited the estate – as from its autobiography we know – he promised to turn all the possible fortune in the purposes of the Transylvanian culture and education. In the course of time, he was trying to fulfill this promise and most likely he has kept his word. In this spirit, János Kemény organised at Marosvécs between 1926 and 1944 the Erdélyi Helikon meeting which brought together a growing number of Transylvanian writers. The meeting was held each year, which brought something new: book publishing, journal publishing, literary evenings, together with the Romanian and Saxon writers. First year of these meetings János and his scottish-greek wife Augusta Paton set up a foundation of 30 000 lei award, offered each year for the best literary work. The 100.000 lei award was given to Antal Szerb for his work The The History of the Hungarian Literature. He created at Marosvásárhely/Tirgu Mures the so called “bed foundation” at the Czakó-clinic, for treatment of writers and artists for case of illness,  he set up memorial for the two Bolyai, placed a memorial at the  birthplace István Petelei (unveiled in 1928 by János Kemény on September 13). In addition to art, for a  variety of purposes, was willing to spend large sums of money, if he considered that it is for the progress of humanity, and for promoting improvements in human well-being. These included the construction of schools and libraries, to create globetrotters travel funding, and even Asbóth Oscar's Rolls Royce helicopter engine is financed by him, whose machine rose high into the air on 9 September 1928.
The spirit of patronage that represented János, culminated in case of the theater.
Let it be here his confess to Sütő:
“Before his death, he told me: "- thirty-five thousand acres of forest I sold for the theater, but please do not tell my wife about this." I did not speak. Just now I tell to everyone that - to my knowledge - the Transylvanian culture-history didn’t know greater patron than János Kemény was.”