All of the above dates are given in Terran Standard (Post Diaspora) Reckoning. Like all extra-Solar systems settled during the Diaspora of Man, the Manticore System found it necessary to create its own calendar to reflect the axial and orbital rotations of their new home, but in the Manticorans' case the situation was complicated by the fact that whereas most star systems are fortunate to have a single habitable world, their distant binary system possessed three of them, each with its own day and year.

As the rest of humanity, Manticorans use Standard Seconds, Minutes, and Hours, and Old Earth's 365.26-day year serves as the "Standard Reckoning Year," or "T-year," the common base to which local dates throughout known space are converted for convenience in dealing with inhabitants of other star systems. Like most extra-Solar polities, the Star Kingdom of Manticore's history texts follow the convention of counting years "Post Diaspora" (ie., in T-years from the year in which the first interstellar colony ship departed Old Earth) as well as in terms of the local calendar.

The Kingdom's Official Reckoning of dates is based on the rotational and orbital periods of Manticore-A III, the planet Manticore. This calendar is used for all official records, but doesn't really work very well for the seasons of any planet other than Manticore itself. Accordingly, both Sphinx (Manticore-A IV) and Gryphon (Manticore-B IV) have their own, purely local calendars, which means that a single star system routinely uses no less than four calendars (including Standard Reckoning). Needless to say, date-conversion software is incorporated in virtually every Manticoran computer.

The Kingdom's planetary days and years are:

The clocks of each planet count time in full 60-minute Standard Hours (or T-hours), with an additional, shorter "hour" called "Compensate" (or, more commonly, simply "Comp") to make up the difference. Thus the Planet Manticore's day consists of 22 hours (numbered 01:00 to 22:59) plus a 27-minute-long Comp, while Sphinx's day consists of 25 hours (numbered 01:00 to 25:59) plus a 37-minute Comp. The planetary week is seven planetary days long in each case, and Manticore's day is used aboard all Royal Navy vessels.

The official year of the Kingdom is 673 days long, with a leap year every third year. It is divided into 18 months, 11 of 37 days and 7 of 38, alternating for the first 6 and last 8 months, named (simply, if rather unimaginatively) First Month, Second Month, Third Month, etc., with a leap year (1 extra day in 4th Month) every third year. The Gryphon local year is also divided into 18 months (16 of 36 days and 2 of 37 days) with the extra days in Ninth and Tenth and one extra day in Eleventh Month every other local year. The Sphinxian year, however, is divided into 46 months, 35 of 39 days and 11 of 38 days (the shorter months fall in even-numbered months from Twelfth to Thirty-Second), with a leap year every 7 years with an extra day in 15th Month. All of these calendars are reckoned in "Years After Landing" (abbreviated al), dating from the day (March 21, 1416 pd) the first shuttle from the colony ship Jason touched down on the present-day site of the City of Landing. Obviously, this means that each planet's local year is a different "Year After Landing" from any of the others. Thus Honor Harrington's orders to Fearless, dated Fourth 25, 280 al (using Official Manticoran Reckoning, or the Manticore planetary calendar), were also written on March 3, 1900 pd (Standard Reckoning), and on Second 26, 93 al (using the local Sphinxian calendar). This plethora of dates is a major reason Manticorans tend to convert time spans into T-years even in domestic matters.

Roger I 1471—1474 pd (32—34 al)

Elizabeth I 1474—1507 pd (34—53 al)

Michael 1507—1539 pd (53—72 al)

Edward I 1539—1544 pd (72—74 al)

(boating accident; succeeded by sister)

Elizabeth II 1544—1601 pd ( 74—107 al)

David 1601—1642 pd (107—131 al)

Roger II 1642—1669 pd (131—147 al)

Adrienne 1669—1681 pd (147—154 al)

William 1681—1690 pd (154—158 al)

(assassinated)

William II 1690—1741 pd (158—188 al)

Caitrin 1741—1762 pd (188—200 al)

Samantha 1762—1785 pd (200—214 al)

George 1785—1802 pd (214—224 al)

Samantha II 1802—1857 pd (224—255 al)

Roger III 1857—1883 pd (255—270 al)

Elizabeth III 1883 pd—present (270 al—present)

Manticoran political parties began as factions in the House of Lords and, in the Lords, retain much of their original factional nature.

The Constitution adopted following the Plague intended to place government primarily in the hands of the aristocracy, who would dominate the House of Lords (the senior branch of the Parliament) and the Royal Council, but things actually worked out somewhat differently. Although Roger Winton had been a very strong planetary administrator, it is improbable that the drafters of the Constitution truly intended for the Crown to acquire a firm grip on the executive authority. Elizabeth I, however, was a very shrewd administrator, and she quickly observed that the original Manticoran peerage comprised a group of spokesmen for competing interests rather than statesmen. By playing the interests of the various factions within the Lords off against one another, Elizabeth was able to establish (among other things) that the Prime Minister and all non-hereditary members of the Royal Council served at her pleasure. The Lords had the right to advise and consent on initial appointments, but she had the power to dismiss them at any time, and she could not be forced to accept anyone else's choice for any of those positions. With that principle firmly enshrined in the unwritten portion of the Star Kingdom's Constitution, Crown dominance of the government was established.

As a ruling house, the Wintons have proven extremely capable. Indeed, their only realistic competition as a dynasty has come from the Andermani Empire, and for all its undisputed accomplishments, the Anderman Dynasty has always suffered from a potentially dangerous degree of eccentricity which has never afflicted the House of Winton.

Nonetheless, it eventually dawned on the members of the peerage that the Crown had assumed (some might say usurped) much of the political power the Shareholders had intended to reserve for themselves and their children. It also occurred to them that Elizabeth had enjoyed the strong support of the House of Commons in her maneuvers, for the Commons (elected primarily by the yeomen and zero-balancers imported after the Plague) had recognized that the Constitution stacked the deck against them. In particular, the fact that both houses enjoyed the mutual power of veto but that members of the Lords need not stand for election, gave the upper house enormous leverage in any dispute between them.

Once recognition set in — and once the immediate factional squabbles of the early settlement and post-plague period had been settled — the Lords began to evolve genuine parties. For the most part, they grew up around the old personal factions, but they were also differentiated by clear ideological differences, and as they solidified, they reached out to the Commons for allies. Because of their advantages in not needing to stand for reelection, members of the aristocracy continue to head most of the political parties to this day, but they have learned the hard way to listen to the Members of Parliament from the Commons, as well. Most (though by no means all) Manticoran aristocrats have a fairly strong sense of noblesse oblige (those who do not are among the most self-centered and intolerant of the known universe), but without the input of their allied commoner MPs, the aristocratic leadership of any of the parties would quickly lose touch with the majority of the Star Kingdom's population and suffer for it the next time the House of Commons called a general election.