>>9194104 They displace existing magnates and maintain retinues of human male knights that they keep in line with sex. More powerful/attractive Amazonians can attract retain a larger retinue, thus increasing their power
>>9194115 Naturally however, the larger the retinue, the less likely any of her household knights is to father her children, so it's a bit of a give and take. If an Amazonian is too greedy and tries to maintain too large of a household, she may have trouble maintaining loyalty.
>>9194121 Male children of Amazons are anatomically normal humans (the Amazonians themselves average ~6'3"- 6'9" in height) and, contrary to popular mythology, are actually are a prized asset for the Amazonian. While Amazonians do not have "marriage," per se, a male child may be trained in the arts of war and enter the household of an allied Amazonian to strengthen ties. Conversely, she may retain a son in her own manorial estate, perhaps even obtaining an education for him, and provide him a human wife from among her serfs. A related male can be extremely useful in helping to run the economics of the estate, manage serf labor, and provide additional local blood ties to the local commoners which helps solidify her rule over time.
At this point it should be noted that Amazonians do not have concealed ovulation, so they cannot "trick" their retinues with non-reproductive sex like perfidous human women. When an Amazonian is in heat, her breasts and buttocks may swell by nearly double their normal size and her facial features soften and become more feminine. Amazonians breed seasonally, to coincide with the war season, and have a rapid 6 month gestation period, after which they breastfeed for a short time before handing the child over to human female wet nurses. In typical European climates, the Amazonians enter their fertility window in mid to late autumn, are pregnant throughout the winter, and give birth in early spring, after which time they shed a large amount of fat and return to combat shape. Their bodies can endure multiple births and recovery periods with minimal ill effects while they are in their prime.