Is Theory Of Relativity given by Einstein?

He'd been very secretive about his family life, and the secrecy had prevailed after his death.
He left behind some 40,000 documents in Princeton, and they had been locked up like the Dead Sea Scrolls until the late 1980s when the Hebrew University (which owns Einstein's copyright) and the Princeton University Press began to publish them.

In the course of their investigation the scholars on the Einstein Papers project found love letters that he had written to Mileva(first wife) when they were both students in Zurich in the late 1890s, and the years just after the turn of the century. It was clear from these letters that Einstein had talked about the issues of relativity, and atomic theory and everything else, but especially relativity, with Mileva.

There were statements in these letters such as "how happy and proud I will be when our work on the relative motion is complete." It sounded provocative to some renegade historians and they made a fuss about Mileva having been deprived of her share of credit.

Actually if you read these letters in full and in context, that statement has more emotional content than intellectual content. He was reassuring her about the state of their relationship. Nobody had really tried to tell the story of where general relativity had come from, and the very winding path that he had taken to it, for a popular audience.