Leonhard Euler (1707-1783) published more than 800 books and articles, many of which are among the most important mathematics ever discovered. Over 80 of his papers are about series, and two of his books deal primarily with series. Some of his results appear in "blockbuster" papers that make a huge contribution in just a single paper. Examples include the Basel Problem paper in which he evaluates zeta(2), Philip Naudé's problem in which he solves many problems of partition numbers, his paper on the Sum-Product formula for the zeta function and his paper on the foundations of continued fractions. There are other ideas, though, where the results are spread out over several papers, like the Euler-Mascheroni constant and Euler-Maclaurin series, were developed over several papers and several years. We will follow some of these lesser threads and trace a few of these longer stories, and connect them to the mathematical and scientific life in the 18th century.