The son of Heinrich Melchior Muhlenberg, he was born in Trappe, Pennsylvania. He was educated at Franckesche Stiftungen in Halle starting in 1763 and in 1769 at the University of Halle. He returned to Pennsylvania in September 1770 and was ordained as a Lutheran minister. He served first in Pennsylvania and then as a pastor in New Jersey. He received a Doctor of Divinity degree from Princeton University.
He served as the pastor of Holy Trinity Church in Lancaster, Pennsylvania from 1780 through 1815. In 1787, he was also made the first president of Franklin College. 1779 he retired and devoted himself to the study of botany. He is best known as a botanist. Muhlenbergia, a well-known genus of grasses, was named in his honor. His chief works are Catalogus Plantarum Americae Septentrionalis (1813) and Descriptio Uberior Graminum et Plantarum Calamariarum Americae Septentrionalis Indiginarum et Cicurum (1817).
Muhlenberg discovered and identified the bog turtle while conducting a survey of plants in Lancaster County, Pennsylvania. In 1801 the turtle was named Clemmys muhlenbergii in his honor, (with a common name of Muhlenberg's tortoise). However, the species' common name was changed to bog turtle in 1956, as the practice of naming an organism's common name after individuals became less popular.
Muhlenberg was the brother of Frederick and Peter Muhlenberg, father of Henry A. P. Muhlenberg and Frederick Augustus Hall Muhlenberg, a physician, who was the father of Frederick Augustus Muhlenberg, the first president of Muhlenberg College.
- Franckesche Stiftungen
- Archiv der Franckeschen Stiftungen, AFSt/S B I 94, 575-577
- Chisholm 1911, p. 957.
- Thurston & Moore 1905, p. 90. sfn error: no target: CITEREFThurstonMoore1905 (help)
- Crable, Ad (2009-09-08). "Big threat to a little turtle". Intelligencer Journal. Archived from the original on 2013-01-27. Retrieved 2009-09-15.
- Beolens, Bo; Watkins, Michael; Grayson, Michael (2011). The Eponym Dictionary of Reptiles. Baltimore: Johns Hopkins University Press. xiii + 296 pp. ISBN 978-1-4214-0135-5. ("Muhlenberg", pp. 184-185).
- Brubaker, Jack (2014-10-31). "Noted portrait painter Eichholtz deserves grave recognition". Lancaster Online. Retrieved 2014-11-08.
- IPNI. Muhl.
- Chisholm, Hugh, ed. (1911). Encyclopædia Britannica. 18 (11th ed.). Cambridge University Press. pp. 956–957. This work in turn cites:
- John M. Maisch, G. H. E. Muhlenberg als Botaniker (1886)
- Solomon Erb Ochsenford. Muhlenberg College: A quarter-centennial memorial (1792) p. 172-173.
- This article incorporates text from a publication now in the public domain: Gilman, D. C.; Peck, H. T.; Colby, F. M., eds. (1905). . New International Encyclopedia (1st ed.). New York: Dodd, Mead. p. 90.