Brother of Jared

In the Book of Mormon, the Brother of Jared is the most prominent person in the account given in the beginning of the Book of Ether. The Brother of Jared's name is not given in the text of the Book of Mormon, but Joseph Smith stated in 1834 that it was Mahonri Moriancumer.

Name

In an 1835 letter, Oliver Cowdery parenthetically gives the name of the brother of Jared as "Moriancumer," which appears in the Book of Ether in the Book of Mormon only as a place name. A later account describes an 1834 statement by Joseph Smith in which he said that the brother of Jared's name had been revealed to him as "Mahonri Moriancumer":
Etymologies have been proposed but remain largely speculative.
According to Daniel H. Ludlow, it is not clear why the name of the Brother of Jared does not appear in the Book of Mormon. However, the following are possible reasons:

The Brother of Jared may have omitted his name out of modesty ;
The Book of Ether is clearly a family record of Jared, not the Brother of Jared; Ether, the final writer and perhaps the abridger of the record, was a descendant of Jared and might naturally have emphasized the achievements of his direct ancestor rather than the brother of his ancestor;
Moroni may have omitted the name in his abridgment because of difficulty in translating the name into the Nephite language;
In Ancient Rome, damnatio memoriae meant names were intentionally deleted from the public record. Ancient Egyptian factions also expunged names and statues of heretical rivals. In Ether 11:17–18, a direct descendant of the Brother of Jared, and rival king, is also not named.