The Union of the Crowns era Stuarts sort of implode over a relatively short period of time. They were only in-charge of England between 1603 and 1649 and 1660 to 1714 totaling 103 years and were incredibly unstable or actively at loggerheads with much of the leadership class for almost all of that time to the point that the second king of that union was executed by an assemblage of his own subjects for basically being crap at his job and failing to know when to settle for what he had. The direct line went into exile in 1688, never to be restored despite several attempts and eventually die out in 1807 and the secondary female line died out through a lack of heirs over the course of 26 years - only to be replaced by distant cousins because Parliament said so - whose female line descendents are still on the throne.
The Cromwell dynasty should also be counted, 1649-1660. Failed to create a viable alternative to the Stuarts, failed to settle any of the major issues in the state, failed to eliminate the concept of kingship and resorted to all but coping it for lack of a better option, fought what was to them godly civil wars that solved absolutely nothing and only made things much worse and ultimately unravelling over the course of about a year resulting into the restoration of their great enemies the Stuarts in 1660 with the support of one of their own henchmen George Monck, then richly rewarded with a Dukedom.
Much like the second half of the 15th century in England, the 17th century right across the Isles is just a dumpster fire from start to finish.
The Cromwell dynasty should also be counted, 1649-1660. Failed to create a viable alternative to the Stuarts, failed to settle any of the major issues in the state, failed to eliminate the concept of kingship and resorted to all but coping it for lack of a better option, fought what was to them godly civil wars that solved absolutely nothing and only made things much worse and ultimately unravelling over the course of about a year resulting into the restoration of their great enemies the Stuarts in 1660 with the support of one of their own henchmen George Monck, then richly rewarded with a Dukedom.
Much like the second half of the 15th century in England, the 17th century right across the Isles is just a dumpster fire from start to finish.