The Seljuks conquered Jerusalem in 1071. Their brutality and interference with pilgrimage led directly to the Crusader's conquest, which lasted (in Jerusalem) from 1099 - 1187. Thus the ephemeral Christian occupation lasted 3 times as long as the Seljuk occupation you seem to think particularly significnt.
From 1187 to 1516 Palestine was controlled by the Ayubids (Kurds) and then by the Mamluks (a caste of military slaves who were admittedly mostly Turkish in origin). They were not particularly Turkish in culture or language, as they were thoroughly arabized by their upbringing.
The Turks, who took over about 700 years ago and ruled the land up until about World War 1
Why not admit it. The author is just plain wrong. "About 700 years ago" would be 1300 or so. He was off by over 200 years, since "the Turks" in general usage refers to the Ottomans, who controlled Palestine for most of the period 1516 to 1917. 1516 is not "about 700 years ago."