The family name “Loeb” is oddly entangled with lions and Napoleon.
While most surnames have a generic, readily-searchable origin story, the story of the name Loeb in this family is very specific. The first Loeb in the family arrived in the United States on December 23, 1848: Jewish immigrant Emmanuel Loeb from Alsace, France. Emmanuel was a young man, born in 1827 in the tiny town of Ingwiller where his family had been for at least three generations. But the name of his paternal grandfather was not Loeb.
Until the early part of the 19th century, the Jewish residents of France did not have fixed surnames, so the last name of a son or daughter might not match that of their parents. Emmanuel’s grandfather Jacques used the surname “Loewel.” When Napoleon took control of France at the turn of the 19th century, he allowed the Jews to become citizens of France and to live in cities, when before they had been restricted to dwelling in the countryside and allowed only limited occupations. He also required them to choose fixed family surnames. While some Jews chose to retain whatever surname they were using, many did not. Jacques Loewel and his family chose a shorter variant of Jacques’ surname, and thus he, his son David (Emmanuel’s father), and his other children became the first in this family of Loebs to use that name.
The rationale for the surname goes back to Jacques’ father, Juda. Juda was named for one of the twelve sons of Jacob from the Old Testament where he was compared to a lion, and thus “lion” became a kinnui, or equivalent name for Juda. Others of Jacob’s sons had similar kinnuim: the wolf for Benjamin, the doe for Nephtali; these names were often used interchangeably with the given names. In translation in local languages, these kinnuim became the basis for many surnames. For example, “Cerf,” “Hirsch,” “Hersch,” and “Herschel” were derived from Nephtali’s kinnui. “Loewe” was German* for lion, with variants “Loewel” and “Loeb” among others.
That is how you get to Loeb from Lion and Napoleon.
For more detail, attached is a PDF of Louisville Family Loeb 2011, with the entire story of the Emmanuel Loeb’s origins and family in the U.S.
*Note: While the name “Loeb” has German roots, Emmanuel spoke French. The influence of German in the Alsatian Jewish community may have several sources, including the location adjacent to German-speaking areas of Europe, the migration of Jewish families from German-speaking lands, and the frequent tussle between warring armies over the Alsace region.