The first ever Nations League kicks off with Double Matchdays in each group in September, October and November 2018 with teams in Leagues A and B and League C Group One playing 4 matches (with 2 byes) and teams in all other Groups playing 6 matches with no byes.
Group winners in League A will play a Final Four mini-tournament between 5-9 June 2019 to decide the 2018-19 Nations League champion - these matches will overlapo with the beginning of the African Cup of Nations and Cop America tournaments which both run 7-30 June.
Results will impact seeding for the Euro 2020 Qualifying as well as establishing rankings for Euro 2020 qualifying playoff positions for the 16 teams that playoff for positions 21-24. Promotion and relegation will apply between Leagues as described at
https://en.wikipedia.org/wiki/2018%E2%80%9319_UEFA_Nations_League LEAGUE A Group One: Germany, France, Netherlands (Germany and France clashed in the 2016 Euro Semi Finals, France and Netherlands played in the same 2018 WCQ Group)
Group Two: Belgium, Switzerland, Iceland
Group Three: Portugal, Italy, Poland (Portugal and Poland chased in the 2016 Euro Quarter Finals)
Group Four: Spain, England, Croatia (Spain and Croatia clashed in the 2016 Euro Group Stage)
LEAGUE B Group One: Slovakia, Czech Republic, Ukraine
Group Two: Russia, Sweden, Turkey
Group Three: Austria, Bosnia-Herzegovina, Northern Ireland
Group Four: Wales, Ireland, Denmark (Wales &Ireland played in the same 2018 WCQ group, and Denmark & Ireland clashed in the 2018 WCQ playoffs)
LEAGUE C - note teams in Group One only will have 2 byes Group One: Scotland, Albania, Israel (Albania and Israel played in the same 2018 WCQ Group)
Group Two: Hungary, Greece, Finland, Estonia (Greece and Estonia played in the same 2018 WCQ Group)
Group Three: Slovenia, Norway, Bulgaria, Cyprus
Group Four: Romania, Serbia, Montenegro, Lithuania (Romania and Montenegro played in the same 2018 WCQ Group)
LEAGUE D Group One: Georgia, Latvia, Kazakhstan, Andorra (Latvia and Andorra played in the same 2018 WCQ Group)
Group Two: Belarus, Luxembourg, Moldova, San Marino (Belarus and Luxembourg played in the same 2018 WCQ Group)
Group Three: Azerbaijan, Faroe Islands, Malta, Kosovo
Group Four: Macedonia, Armenia, Liechtenstein, Gibraltar