The Excalibur was ordered in an initial block of four, constructed in parallel between 2234 and 2236: Excalibur, Enterprise, Curtana, and Durandal. The ships proved to be of major tactical benefit to Starfleet's general roster, being both more heavily shielded than the Newton and substantially more dangerous. After a year-long shakedown that resolved problems with the new torpedo launchers and further streamlined the thruster assemblies a further order of eight ships were made: Tizona, Caladbolg, Joyeuse, Kusanagi, Clarent, Hauteclere, Tyrfing, and Hrunting. All were commissioned in 2238 and entered service the following year.
The outbreak of open war with the Klingon Empire in the spring of 2240 threw Starfleet on the back foot, and further orders of starships with secondary tactical roles were suspended. Instead in 2241 a further six Excalibur-class vessels were ordered and entered production, those being Dyrnwyn, Damocles, Dainsleif, Gram, Naegling, and Fragarach. The crash-builds saw the ships launch in late 2243 in time for the counteroffensive of early 2244.