Elizabeth Shelby

Elizabeth Paula Shelby was a female human Starfleet officer born in Lawrence, Kansas in 2336 to Brian and Anita Shelby. 

Family
Captain James T. Kirk slept with her great-great-great-grandmother, her great-great-great-great-aunt, and her great-great-grandmother. 

Her parents have a house in Silver Spring, Maryland on Earth. 

Starfleet Academy
Shelby came from a Starfleet family (both parents were admirals), and herself entered Starfleet Academy in 2354. While there, she was romantically involved with fellow cadet and long-time friend, Vincent Wexler. Their relationship ended during their time at the Academy, and Shelby thereafter found herself in a relationship with Wexler's roommate, Cadet Mackenzie Calhoun. Shelby and Calhoun ended their relationship after taking part of the Kobayashi Maru scenario. Shelby decided to take an extra year of Academy study, and graduated in 2358. 

Early career
Shelby's first assignment out of the Academy was as an ensign aboard the USS Repulse (NCC-2544). She served on four other ships following that assignment, and by 2366, was a full grade lieutenant serving as chief engineer of the USS Yosemite (NCC-19002). By this time, she had decided that she wanted to move from engineering to command, and was frustrated by her inability to do so. (SS NF (All That Glisters...))

The Borg
On stardate 43095.1, Shelby led the Yosemite's investigation of the loss of Science Outpost D5. Shelby was able to determine beyond doubt that the outpost had been destroyed by the Borg, giving Starfleet the first positive confirmation of their intrusion into the Alpha Quadrant. Her work on this mission resulted in her promotion to Lieutenant Commander and transfer to Starfleet Tactical. (SS NF (All That Glisters...))

In late 2366, on stardate 43992.6, Shelby was on board the USS Enterprise (NCC-1701-D) as part of her duties spearheading Starfleet's defenses against the Borg. After Captain Jean-Luc Picard was assimilated by the Borg, Shelby was made Enterprise first officer on stardate 44002.3, despite the friction between her and Captain William T. Riker. Once the Borg attack on Earth was averted and Picard recovered, Shelby was transferred to Starfleet Headquarters, where she would oversee the rebuilding of the fleet. 

By mid-2367, Shelby was first officer of the USS Chekov (Excelsior class) under the command of Captain Morgan Korsmo. The Chekov, the Enterprise, and the USS Repulse (NCC-2544) became involved in a battle between the Borg and an ancient Doomsday machine. The Chekov was irreparably damaged in the battle, though Shelby and much of the crew survived. 

The Excalibur
Shelby, Korsmo, and many of the Chekov's crew were later assigned to the USS Excalibur (NCC-26517) in early 2368. In 2369, the Excalibur had a skirmish with a Borg scout ship, which removed a section of the ship's hull, and took three crew members with it. (SS NF (Making a Difference))

In 2370, Admiral Nechayev considered assigning Shelby to Deep Space 9 as commanding officer after Benjamin Sisko was believed lost in the Gamma Quadrant. Sisko returned safely and Shelby was not assigned to the station. Nechayev thought she would be disappointed at not getting the post. 

In 2371, the Excalibur took part of a rescue of Starfleet officers William T. Riker, Deanna Troi, and Worf along with Worf's son, Alexander Rozhenko from the Romulan, Sela. 

In 2371, Shelby, acting in her role as a specialist in tactics for fighting the Borg, relayed instructions and mission parameters to Jean-Luc Picard, when Picard was assigned to work with a Borg-resurrected James T. Kirk.

The Excalibur was present when the Borg attacked Earth in 2373. The Excalibur fought bravely, but in the end, she was disabled and unable to assist with the destruction of the Borg vessel. Captain Korsmo was killed in the battle (SS NF (Making a Difference)).

Mackenzie Calhoun
Shelby remained as Excalibur first officer when, following the fall of the Thallonian Empire, command was given to her former fiancé, Captain Mackenzie Calhoun. In addition to the tension arising from their shared history, Calhoun's maverick instincts clashed with Shelby's by-the-book style, and the two were constantly at odds during the three years they served together. All this time, Shelby denied any residual feelings toward Calhoun.

In early 2376, the Excalibur was destroyed in a warp core breach caused by a computer virus. The entire crew was able to escape, except presumably, Calhoun. Only then could Shelby admit her romantic feelings for him, but she resolved to move on with her life. 

Following the loss of the Excalibur, Shelby was promoted to captain and given command of the USS Exeter. While she initially hoped this new ship would provide a more by-the-book environment, Shelby found her command style had been significantly influenced by her time serving with Calhoun, and that the Exeter was not a good fit for her. When the new USS Excalibur (NCC-26517-A) was launched in late 2376, Shelby was reassigned as its commanding officer with Calhoun's old crew intact.

However, at the dedication of the Excalibur-A, Mackenzie Calhoun reappeared, after having been marooned on the planet Yakaba. Calhoun immediately proposed marriage to Shelby. After punching him, Shelby accepted. They were married on the bridge of the Excalibur-A in a ceremony officiated by Captain Jean-Luc Picard. 

Following their Starfleet wedding ceremony, Shelby and Calhoun traveled to Xenex, where Shelby underwent a series of physical and psychological trials before they could be wed under Xenexian tradition. (SS NF (A Little Getaway))

The Trident
After their return from Xenex, Shelby took command of the USS Trident (NCC-31347) and was assigned to patrol Sector 221-G along with the Excalibur. In the first months of Shelby's command, the Trident participated in the Gateways crisis, battled the God-like "Beings." 

Shelby was also instrumental in revealing the telepathic manipulation of the Federation by member species, the Selelvians. This revelation lead to a short war between the Federation and the Selelvians, in alliance with the Tholian Assembly. Shelby and the Trident served with distinction during this brief conflict.

At one point during the conflict, Shelby and Lieutenant Soleta were attacked by a group of Orion mercenaries that were working for the Selevians. Soleta incapacitated Shelby with a Vulcan nerve pinch, and attacked the Orions single-handedly, nearly sacrificing her own life to save Shelby. (SS NF (Pain Management))

Admiral Shelby
Following the war with the Selelvians, Shelby was promoted to Admiral and was placed in command of Space Station Bravo following the retirement of the station's previous commander, Admiral Frank Kittinger. (SS NF (Pain Management); )

In 2379, Shelby, with the cooperation of the Trident's new commander, Captain Katerina Mueller, defied orders from Admiral Edward Jellico and took the Trident to the planet Priatia following the disappearance of her husband and the Excalibur.

Her actions were pivotal in defeating the extra-dimensional race known as the Teuthis, who were attempting to incite war in the New Thallonian Protectorate and destabilize the area for conquest.

In 2381, during that year's Borg crisis, Shelby was part of a meeting at Starfleet Command Headquarters via subspace communications to discussion potential strategy against the Borg. Shelby was insistent that continued use of the transphasic torpedoes wouldn't allow the Borg to adapt, as it destroyed in only one shot. Shelby feared leaving the core worlds undefended if Seven of Nine was able to convince Starfleet to move all their forces to the Azure Nebula. 

Alternate timelines
In the anti-time future experienced by Jean-Luc Picard, Shelby was still a captain in 2395, in command of the USS Yorktown (NCC-61137).