Complex sentence: At the Fens of Serech where during the Dagor-nuin-Giliath the Noldor had destroyed the Orcs the Noldor now found themselves trapped, and Finrod would have been killed but for a sortie by Barahir, who descended from Dorthonion and rescued the Elven lord.
Split into simpler sentences: At the Fens of Serech where during the Dagor-nuin-Giliath the Noldor had destroyed the Orcs. The Noldor now found themselves trapped, and Finrod would have been killed but for a sortie by Barahir, who descended from Dorthonion and rescued the Elven lord.