Complex sentence: Elagabalus' claim was not without contention, however, as several pretenders made their own bids for "the purple" including Verus the commander of Legio III Gallica and Gellius Maximus the commander of Legio IV Scythica.
Split into simpler sentences: Elagabalus' claim was not uncontested, however, as several others made their own bids for "the purple". These included Verus the commander of LegioIII Gallica and Gellius Maximus the commander of LegioIV Scythica.