Answer:

GER

Answer	Crossword Clue
GER	NATO member
GER	Neighbor of Neth
GER	2014 World Cup winners, who defeated ARG and BRA

GER	Eur. language
GER	Lang. in which "Rapunzel" was written
GER	Teutonic (abbr.)
GER	Neighbor of Pol.
GER	Between Holl. and Pol.
GER	Lang. of Ulm
GER	Leipzig lang.
GER	EU member

GER	Lux. neighbor
GER	Teut.
GER	Eur. country
GER	Lang. that gave us "lederhosen"
GER	Lang. that gave us "flak"
GER	Neth. neighbor
GER	Fr. neighbor
GER	Jung's tongue: Abbr.

GER	Pol. neighbor
GER	31-Down's country: Abbr.
GER	Cologne's country: Abbr.
GER	Hamburger's home?: Abbr.
GER	Switz. neighbor
GER	Aus. neighbor
GER	Berlin's country: Abbr.
GER	1939 Pol. invader

GER	Nation next to Lux.
GER	BMW's home
GER	Essen's country: Abbr.
GER	Land on the Baltic: Abbr.
GER	Berlin's land: Abbr.
GER	Like BMWs: Abbr.
GER	Luther's lang.
GER	Neighbor of Aus.

GER	Where BMW was born
GER	Lang. of Luther
GER	North Sea country: Abbr.
GER	Whence BMWs
GER	Berlin's land (abbr.)