Is the construction of $\mathbb{R}$ by Cauchy sequences due to Cauchy? For that matter, are Cauchy sequences due to Cauchy?

Question

A little bit of cursory searching around on Wikipedia reveals only that Cauchy sequences are named after Cauchy—but I already knew that.

Answer 1

You can find a reasonably detailed sketch of the history here. The first Cauchy sequence type of construction was given by Méray, though there had been a partial anticipation by Bolzano. Much closer is the construction of Heine, and of Cantor. The constructions of the last three appeared in the period 1869-1872. Cauchy has no direct connection with the constructions, he worked with Cauchy sequences of reals.