Lemuelites were a subdivision of Lamanite

Lamanite

According to the Book of Mormon, a Lamanite is a member of a dark-skinned nation of indigenous Americans that battled with the light-skinned Nephite nation...

s, a purported people of the ancient Americas referenced in the Book of Mormon

Book of Mormon

The Book of Mormon is a sacred text of the Latter Day Saint movement that adherents believe contains writings of ancient prophets who lived on the American continent from approximately 2600 BC to AD 421. It was first published in March 1830 by Joseph Smith, Jr...

. To save time and prevent confusion those who were sought to destroy Nephi's people

Nephite

According to the Book of Mormon, a Nephite is a member of one of the four main groups of settlers of the ancient Americas. The other three groups are the Lamanites, Jaredites and Mulekites. In the Book of Mormon, the Nephites were a group of people descended from or associated with Nephi, the...

 were often just called Lamanites.

Origins

In the journey in the wilderness, there is a reference to Lemuel

Laman and Lemuel

In the Book of Mormon, Laman and Lemuel are the two eldest sons of Lehi and the older brothers of Sam, Nephi, Jacob, and Joseph. According to the text, they lived around 600 BC. They were notable for their rebellion against Lehi and Nephi, becoming the primary antagonists of the First and Second...

, older brother of Nephi

Nephi

According to the Book of Mormon, Nephi was the son of Lehi, a prophet, founder of the Nephite people, and author of the first two books of the Book of Mormon, First and Second Nephi.- Early life :Nephi was the fourth of six sons of Lehi and Sariah...

 younger brother of Laman

Laman and Lemuel

In the Book of Mormon, Laman and Lemuel are the two eldest sons of Lehi and the older brothers of Sam, Nephi, Jacob, and Joseph. According to the text, they lived around 600 BC. They were notable for their rebellion against Lehi and Nephi, becoming the primary antagonists of the First and Second...

, marrying one of the daughters of Ishmael

Ishmael

Ishmael is a figure in the Hebrew Bible and the Qur'an, and was Abraham's first born child according to Jews, Christians and Muslims. Ishmael was born of Abraham's marriage to Sarah's handmaiden Hagar...

. Also in the Wilderness the wives of the Lehi group bear children; There we have the beginnings of the Lemuel's family, though not referenced as having been called Lemuelites until the ministry of Jacob.

Other references

During the missionary efforts of Ammon

Ammon

Ammon , also referred to as the Ammonites and children of Ammon, was an ancient nation located east of the Jordan River, Gilead, and the Dead Sea, in present-day Jordan. The chief city of the country was Rabbah or Rabbath Ammon, site of the modern city of Amman, Jordan's capital...

 there is a reference to some Lemuelites being converted to the Lord.

Also again there is a reference to them being compounded under the name Lamanites and that Lamanites are made up of Lemuelites, Lamanites, Ishmaelites and dissenters from the Nephites. as in Mormon's time as well.

After the space of the generations of peace, a group called Lemuelites are among those to break away from the church and reject the gospel.