Final answer:
Winterbourne is the person who arrived in Rome and stayed at the same hotel where the Count met Albert.
Step-by-step explanation:
The person who arrived in Rome and stayed at the same hotel where the Count had met Albert is Winterbourne. This information comes from the context of the text provided, where Winterbourne is visiting Rome and is aware of the presence of Daisy and her family, whom he knew from a previous summer at Vevey.
The details within the text suggest a social connection between the characters and imply that Winterbourne is considering renewing his acquaintance with them, especially with Daisy Miller. Mrs. Walker seems to be a mutual acquaintance hosting social events in Rome.
The extract is likely from Henry James's Daisy Miller, where the protagonist, Winterbourne, encounters various characters from his past travels and experiences social interactions in the expatriate community of Rome.