Hi,
I think this refers to Century 9 Quatrain 73. If you ask me it's about King Henry IV of France (King of France 1589 - 1610 so that's 21 years). According to the quatrain he reigned less than an evolution of Saturn, and it takes Saturn 27-29 years to go through all the zodiac signs. So 21 years is less. The white Turban King could be Sultan Ahmed I. King Henry IV and Sultan Ahmed I signed agreement. You can read it all in attached links.
https://en.wikipedia.org/wiki/Henry_IV_of_Francehttps://en.wikipedia.org/wiki/FoixCENTURIE IX. 73.
The Blue Turban King entered into Foix,
And he will reign less than an evolution of Saturn:
The White Turban King Byzantium heart banished,
Sun, Mars and Mercury near Aquarius
Dans Fois entrez Roy cerulée Turban ,
Et regnera moins evolu Saturne ,
Roy Turban blanc & Bizance cœur ban ,
Sol , Mars , Mercure enƒemble prés la hurne