[sentence (continuative)]、又 + [noun] + も + [predicate] [noun] + であり、又 + [noun] + でもある 又も + [verb]
又~も adds a second fact about the same subject: "and also", "and moreover". 又 opens the added part and も marks the word that is added. The first half usually ends in a continuative form – きごう〜であり, きごう〜く, きごう〜で – and the whole pattern belongs to writing and formal speech.
With a noun or な-adjective, も goes after で: でもある. With an い-adjective, it goes after the 〜く form: やさしく優しくもある.
In modern writing the word is more often spelled in kana, また. The kanji 又 looks older and more formal.
With nothing between them, 又も is an adverb meaning "yet again", usually about something unwelcome. It sounds more dramatic than plain また and is common in news headlines.