From Halopedia, the Halo wiki
A keep, or "manor", is the ancestral home of a Sangheili clan. Though each clan has one, keeps differ greatly based on their role and the position of their inhabitants. The master of a keep is known as an elder. A typical Sangheili state may contain multiple smaller client keeps where the clans inhabiting the state reside, governed by a single keep headed by a kaidon or ocasionally, a Scion. The kaidon's keep serves as an assembly house where the elders from the client keeps convene to decide on matters concerning their state.
A residence for Sangheili to live in and to mate and raise/train their young, the keep has many common rooms for the average inhabitants, but the elder members of the clan reside in larger living quarters for their higher status. Each keep has a "saga wall" where the family saga of the clan is written. Although their architecture may vary greatly, keeps are often constructed of non-Covenant alloys and are built with more traditional items such as stone and wood. Depending on the ranking status of the inhabitants the keep may be decorated with Forerunner alloys. They usually have large courtyards to spar and train.
More powerful keeps are set to rule over a certain state on Sanghelios and reap the benefits of the governed area, which may house a number of client keeps with less power than the kaidon's keep; a council of elders from the kaidon's own keep and the client keeps oversee the kaidon's actions and help him make decisions. While each keep is named after the clan inhabiting it, the clan elders will adopt the name of the state's ruling keep; for example, the elders of Bekan keep bear the 'Mdama title as they reside in the state of Mdama. If in doubt of the current kaidon's leading abilities, the elders may attempt to assassinate the kaidon. This can be achieved through assassins or doing the job themselves, but should they fail the task the plotter will be killed instantly and his family expelled or killed depending on the nature of the attack. Rival clans may take over another's keep, most likely if the rival clan had a keep of their own they would gain dominance over the state and either destroy the enemy keep or have it as a trophy, most notably they may imprison the previous occupants.
The keep will usually be moderately populated by the members of the clan that owns the keep. Other Sangheili would be chosen for their abilities to train the young, general maintenance, horticulture, and their skill at meal preparation. The wife of a keep elder typically holds significant power within a keep concerning family and bloodline matters. Wearing armor around the keep is not customary as most of the inhabitants wear non-combat Sangheili tunics or robes. All Sangheili are given rudimentary combat training and have weapons available in the event they need to take up arms and defend their keep. A kaidon's keep may have dozens of guards for the kaidon's safety, although the kaidon usually removes threats himself to show his battle prowess and that he is a capable leader, for it is believed that a kaidon should be chosen for his skill in battle. The kaidon himself carries his traditional energy sword and plasma pistol sidearm with him at all times.
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