Earlier this year, it was reported by the Associated Press that the Cubs and Cardinals were under consideration for a series in London in 2020. The Red Sox and Yankees will play two games there next month.
Today, this appears to be official:
The #Cubs and #Stlcards have agreed to play in London next summer. The #Yankees and #Redsox play the inaugural series in Europe next month. #Rivalries going overseas.
— Bob Nightengale (@BNightengale) May 16, 2019
It’s also being reported by local writer Bruce Levine:
This is awesome and exciting news.