In January, 1949, Shannon publishes the paper Communication in the Presence of Noise, Proc. IRE, Vol. 37, no. 1, pp. 10-21, available here, which establishes the Information Theory. In this paper, the sampling theorem is presented.
Any references about the history of the sampling theorem, its connection with Fourier theory, would be appreciated.
EDIT1: In C.E. Shannon, Mathematical Theory of Communication, Bell System Technical Journal, Vol. 27, pp. 379–423, 623–656, July, October, 1948, available here, the Sampling Theorem is Theorem 13.