Gallo signed a one-year, $5 million contract with the Nationals on Tuesday, Andrew Golden of The Washington Post reports.
He'll have the opportunity to earn an additional $1 million in incentives. Gallo slashed just .177/.301/.440 last season with the Twins, although he did pop 21 home runs over 332 plate appearances. The 30-year-old would appear to be penciled in as the Nationals' regular left fielder, although he could see some action at first base, as well.