Wiktionary
vb. (context transitive English) To hold in subjection; hence, to oppress.
Usage examples of "keep under".
He could keep under cover part of the way, and much of the part above timberline was invisible from below.
It is not in the nature of man to bear the cross, to love the cross, to keep under the body and to bring it into subjection, to fly from honours, to bear reproaches meekly, to despise self and desire to be despised, to bear all adversities and losses, and to desire no prosperity in this world.
But there would be such a shout for new laws that Parliament and Congress would have to do something, so it was best to keep under cover as long as possible.
All his jealousy and sense of personal injury, which he had been hitherto trying to keep under, had leaped up and mastered him.
To keep under the Pope, the Roman barons contributed much, who, being divided into two factions (the Ursini and Colonnesi, in perpetual contention, with their arms constantly in their hands under the very nose of the Pope), they kept the pontifical power very low and infirm.
And there was simply no way to keep under close guard a man whom he intended to load with so much power and authority as well as responsibility.
He's the most blue-collar of us and has a mean streak that he manages to keep under-control.