The originally Orthodox congregation was established in 1898, and it constructed the E. Main Street synagogue building in 1915, and joined the Conservative movement in the 1950s.

"[6][7] By the turn of the 20th century, Ottumwa had fewer than 50 Jewish families, immigrants from Germany and across eastern Europe.

One local Jew had a personal Torah scroll and a private mikvah, but there was no organized community.

By 1919, the Jewish population of Ottumwa had risen to 412 and the congregation had moved one block into the current building.

[9][17][18] In August of that year, the congregation donated its Torah scroll "to a new synagogue forming in South America", and ceased functioning.

The exterior is brick, with an addition in the back holding a kitchen and social hall, built some time in the 1950s.

The sanctuary features a woman's gallery against the south-west wall, built over the front entrance foyer and classroom, although it is rarely used.

The separation of men and women at B'nai Jacob ended when one woman's health problems prevented her from climbing the stairs to the balcony.