The Ministry of Time, by Kaliane Bradley

In the near future the British government has acquired a time travel device and has brought forward several people from the past – 1645 to 1916. Each has a civil servant assigned as a bridge – a minder to help acclimatise them to the present day and report on them to the Ministry. But how will the personal relationships formed affect the present and the future? Especially that between charismatic polar explorer Graham Gore and his unnamed Eurasian bridge. It's an intriguing premise, well constructed and imagined, that turns into something of a mindfuck as the time travel elements turn on themselves.