This sentence seems to have a misprint or error 'cause it doesn't make sense. 

One of the correct versions would be like this: "В своих меморандумах короли угля стали требовать всей Лотарингии; не отставали от них и массовые военно-патриотические союзы, говорившие о захвате новых территорий".

Короли угля и стали в своих меморандумах требовали как минимум всей Лотарингии, не отставали от них и массовые военно-патриотические союзы, говорившие о захвате новых территорий.

The sentence is absolutely ok and doesn't contain any mistake or a typo. You should have posted in the Answers section because it's a question, not a text for correction. And you should also have provided some context — what is the article about? My guess, it's about the situation on the eve of a war.

Now, to the sentence:

Короли угля и стали = kings of coal and steel. It's a bit poetic way to describe industry moguls.

в своих меморандумах = in their memoranda / in their memorandums

не отставали от них = in this context it means "were in agreement", "were doing the same"

In their memoranda, the industry moguls demanded at least the whole of Lorraine; the military-patriotic unions were doing the same by calling for the annexation of the new territories.