Bethel Coopwood was born on May 1, 1827, in Lawrence County, Alabama. He moved to Texas in 1846. In 1847, he enlisted in Bell's cavalry detachment, of Hay's Regiment of Texas Mounted Volunteers, that served along the Rio Grande frontier in the Mexican–American War. In 1854 he moved to California, where he was admitted to the bar, practicing in Los Angeles. In early 1857, following the killing of Sheriff James R. Barton and two men of his posse, by the Flores Daniel Gang, Coopwood led twenty-six El Monte men, as a division of the posse in the manhunt for the gang.  He distinguished himself in the assault on the peak the gang had taken refuge on, up hill, under fire with an injured leg.:2,col.2-3
In the fall of 1857, at the age of thirty he came to San Bernardino as part of a syndicate that purchased the balance of the Rancho San Bernardino from Ebenezer Hanks for $18,000. Hanks had previously purchased a one-third interest in the grant, with Amasa Lyman and Charles C. Rich leaders of the Mormon colonists of San Bernardino from the original grantee José del Carmen Lugo.
On June 15th 1859 he had married, Josephine Woodward and they eventually had fourteen children. In September, he ran for San Bernardino County District Attorney in 1859, but lost by a narrow margin. Soon afterward, Coopwood sheltered Doctor Alonzo Ainsworth in his own home and along with the help his brother David, Mat Welsh and 5 other men defended the doctor from an anti-Mormon mob from El Monte incited by a rival Doctor Frank Gentry. Bethel along with his brother David, and Mat Welsh, were the three men of Ainsworth's defenders wounded in the shootout with Frank Green and the Gentry faction that was the climax of the September 18th - 20th, 1859 "Ainsworth - Gentry Affair."   :95-96  :419-420
In the bitterly contested campaign of 1860, Charles W. Piercy was nominated for member of the 1st District of the California General Assembly by one party, and W. A. Conn the incumbent, by the other. Piercy was elected, but there was a claim of fraud. The accusation was that polls at Temescal, maintained by a resident named James Greenwade, kept open shop for three weeks and that whenever candidate Piercy was in need of more votes, they were furnished from this precinct. The case was taken to court, where the two opposing lawyers, H. M. Willis and Bethel Coopwood, had a fight in court wherein Coopwood sustained a slight wound, but won the case. Coopwood remained in San Bernardino until 1861, as realtor and a lawyer and with an excellent knowledge of Spanish and a number of Californio clients, most of whom were very well off.
In 1861, Coopwood disposed of his interests in California and returned to Texas with his brothers Benjamin and David. He entered the Confederate Army as a captain in the cavalry and served until 1863. In 1861, he formed the San Elizario Spy Company or Coopwood Spy Company, an Independent Volunteer Company of cavalry with men that came with him from California. He commanded the Confederate forces in the Battle of Canada Alamosa, and Skirmish near Fort Thorn the largest of several small battles that occurred in Confederate Arizona along the front with Union held New Mexico Territory. He and his company served in Sibley's New Mexico Campaign. He was ill with smallpox during the Battle of Valverde but recovered in time to join the army at the Battle of Albuquerque and the Battle of Peralta. After the Battle of Peralta he and his Spy Company were responsible for saving the remnants of Sibley's army, 1800 men, from Union pursuit by finding water and a path for them through the rugged mountains west of the Rio Grande to the Mesilla Valley. He was later promoted to Major and then Lt. Colonel before ending his service in the Confederate Army in 1863.
After the Civil War he spent a year in Coahuila. There he was nearly killed and his brother drowned after being shot by troops of Juan Cortina while traveling on the steamboat Bell on the Rio Grande. His claim against Mexico for money for his brothers widow was unsuccessful. He returned to Texas and became recognized as an able lawyer and Spanish scholar in the lower Rio Grande valley. He contributed articles to and wrote book reviews for early issues of the Texas State Historical Association Quarterly, in which he published "Notes on the History of La Bahía del Espíritu Santo" in 1898–99 and "The Route of Cabeza de Vaca" in 1899–1900. Judge Coopwood died in Austin on December 26, 1907.
- Hubert Howe Bancroft, Popular tribunals, Volume 1, History Company, San Francisco, 1887, p.500
- Los Angeles Star, 7 February 1857, p2, col.1-3, Pursuit and Capture of Flores Daniel Gang
- Los Angeles Star, Number 16, 27 August 1859
- Some of the settlers, being Josephites and not in sympathy with Young's policy or the practice of polygamy, remained in the valley, and the remainder of the church property was placed in the hands of Ebenezer Hanks, who had previously purchased a one-third interest in the grant, and who later sold the property to Richard G. Allen. F. L. Tucker, W. A. Conn and Bethel Coopwood. John Brown, James Boyd, History of San Bernardino and Riverside counties, p. 48
- Los Angeles Star, Number 9, 9 July 1859, p.4, col.1, San Bernrdino, June 26th, 1859. Editor Star—.... Quite a fashionable wedding came off here on the-15th inst., Bethel Coopwood, Esq. to Miss Josephine Woodard, both of this city. The ceremony was performed in a very imposing manner, by Elder Seely, at the residence of the bride's father. After the marriage ceremony, the happy pair entertained the guests to an elegant supper, which consisted of all the delicacies and luxuries of the season. On the evening of the 21st inst. Mr. Coopwood gave a grand ball at the American Hotel; the attendance of ladies and gentlemen was greater than I have ever seen at a ball in this place. The ball continued until the dawn of 'morn, all unwilling to leave the festive scene; and when they left it was with heartfelt wishes for the peace and prosperity of the young couple, who had started together upon life's matrimonial path, I wish them a long life and a happy one.
- Los Angeles Star, vol. 9, no. 20 , September 24, 1859, Page 2, Col. 3
- Los Angeles Star, vol. 9, no. 20 , September 24, 1859, Page 2, Col. 1
- Daily Alta California, Volume 11, Number 268, 27 September 1859, p.1, col.2 OUR LOS ANGELES CORRESPONDENCE - September 24
- History of San Bernardino County, California, with Illustrations Descriptive of its Scenery, Farms, Residences, Public Buildings, Factories, Hotels, Business Houses, Schools, Churches, Etc., from Original Drawings, Including Biographical Sketches (San Francisco: Wallace W. Elliott & Co., 1883
- An illustrated history of Southern California, Lewis Publishing, Chicago, 1890
- THE AINSWORTH-GENTRY AFFAIR – Will the real Dr. Gentry please stand up? By Deven L. Lewis, Research by Dorris Lyn Killian and Deven L. Lewis, Tuesday, Nov 3, 2015 The "Dr. Gentry" of the Ainsworth-Gentry Affair of 1859 has sometimes been misidentified as "Thomas Gentry" (who had lived in the cities of El Monte and San Bernardino, California, at the time of the Affair). The attached piece is offered in an attempt to correctly identify "Dr. Gentry" as Franklin Gentry of Arkansas, who was a well-known physician and politician of El Monte.
- John Brown, James Boyd, History of San Bernardino and Riverside counties, p. 148-149 Later in 1861 Piercy was killed in a duel with another assemblyman, Daniel Showalter.
- John Brown, James Boyd, History of San Bernardino and Riverside counties, p. 122
- Jerry D. Thompson, Civil War in the Southwest: recollections of the Sibley Brigade, Texas A&M University Press, 2001.
- Handbook of Texas Online - COOPWOOD, BETHEL.
- CORTINA'S OPERATIONS.; CAPTURE OF THE STEAMER BELL. CORTINA GIVES UP. MATAMORAS GOSSIP. THE CITY OT MEXICO. New York Times, Published: July 17, 1865
- Schedule of American claims against Mexico, presented to the Joint Commission, pp.58-59