Definition: Rewrite each original sentence in order to make it easier to understand by non-native speakers of English. You can do so by replacing complex words with simpler synonyms (i.e. paraphrasing), deleting unimportant information (i.e. compression), and/or splitting a long complex sentence into several simpler ones. The final simplified sentences need to be grammatical, fluent, and retain the main ideas of their original counterparts without altering their meanings.
Input: The Armenian legion was established under the goals of the Armenian national liberation movement and was an armed unit besides the Armenian volunteer units and Armenian militia during World War I which fought against the Ottoman Empire.

The Armenian legion was created under the goals of the Armenian national liberation movement was an armed unit along with the Armenian volunteer units and Armenian militia during World War I.   They fought against the Ottoman Empire.