。
Sōseki was a contemporary of Ōgai.
Literal
Sōseki [topic-は] Ōgai [and-と] same-era [possessive-の] person was.
A literary-historical note about two giants of early modern Japanese literature. 夏目漱石 (なつめそうせき, 1867-1916) is Natsume Sōseki, author of 吾輩は猫である, 坊っちゃん, 草枕, etc. 森鴎外 (もりおうがい, 1862-1922) is Mori Ōgai, author of 舞姫, 高瀬舟, etc. Both are considered foundational figures in modern Japanese literature. 同時代 ('same era, contemporary') is the key compound.