Question: Hex was partially invented by the mathematician of what European nationality?

Context articles: British passport
Piet Hein (scientist)
2009 Solheim Cup
Shannon switching game
Sahrawi nationality law
Y (game)
Feed icon
James McIlroy (athlete)
Havannah
Hex (board game)

British passports are passports issued by the United Kingdom to those holding any form of British nationality.
 There are different types of British nationality, and different types of British passports as a result.
 A British passport enables the bearer to travel worldwide and serves as proof of citizenship.
 It also facilitates access to consular assistance from British embassies around the world, or if also a citizen of the European Union, any embassy of another European Union member state.
 Passports are issued using royal prerogative, which are exercised by Her Majesty's Government.
Piet Hein (16 December 1905 – 17 April 1996) was a Danish mathematician, inventor, designer, author, and poet, often writing under the Old Norse pseudonym "Kumbel" meaning "tombstone".
 His short poems, known as "gruks" or grooks (Danish: "gruk"), first started to appear in the daily newspaper ""Politiken"" shortly after the Nazi occupation in April 1940 under the pseudonym "Kumbel Kumbell".
The 11th Solheim Cup Matches were held August 21–23, 2009 at Rich Harvest Farms in Sugar Grove, Illinois, west of Chicago.
 The biennial matches are a three-day team competition for professional female golfers, pitting the 12 best players born in the United States against the 12 best players of European nationality.
The Shannon switching game is an abstract strategy game for two players, invented by American mathematician and electrical engineer Claude Shannon, the "father of information theory" some time before 1951.
 Two players take turns coloring the edges of an arbitrary graph.
 One player has the goal of connecting two distinguished vertices by a path of edges of their color.
 The other player aims to prevent this by using their color instead (or, equivalently, by erasing edges).
 The game is commonly played on a rectangular grid; this special case of the game was independently invented by American mathematician David Gale in the late 1950s and is known as Gale or Bridg-It.
Sahrawi nationality law is the law of the Sahrawi Arab Democratic Republic (SADR) governing nationality and citizenship.
 SADR is a partially recognized state which claims sovereignty over the entire territory of Western Sahara, but only administers part of that territory.
Y is an abstract strategy board game, first described by John Milnor in the early 1950s.
 The game was independently invented in 1953 by Craige Schensted and Charles Titus.
 It is a member of the connection game family inhabited by Hex, Havannah, TwixT, and others; it is also an early member in a long line of games Ea has developed, each game more complex but also more generalized.
The Feed icon is for indicating that a web feed is available on a web page.
 It was originally invented for the use of RSS, but it is also common for Atom and other web feeds now.
 The icon is normally orange, with hex code #FA9B39.
 The original icon was created by Stephen Horlander, a designer at Mozilla.
James McIlroy (born 30 December 1976) is a British middle distance runner.
 He initially represented Ireland before changing his nationality.
 When he was 21 years old he showed great promise by finishing fourth over 800 metres in the 1998 European Athletics Championship having taken 14 seconds off his personal best in only 13 months.
 Serving a 1-year ban for changing nationality McIlroy still produced the 3rd fastest British All - time 1000 metres behind Sebastian Coe and Steve Cram when finishing 4th in Rieti, (Italy).
 In 2000 he won his first of five British Championships and representing Great Britain made the Sydney Olympics semi - final .
 Representing Northern Ireland McIlroy managed 6th at the 2002 Manchester Commonwealth Final after getting badly boxed in.
 From 2002 onwards McIlroy spent considerable time in South Africa training and after being injured for most of the 2003 - 4 season he again finished 4th at the European Indoor Championships in Valencia in 2005.
Havannah is a two-player abstract strategy board game invented by Christian Freeling.
 It belongs to the family of games commonly called connection games; its relatives include Hex and TwixT.
 Havannah has "a sophisticated and varied strategy" and is best played on a base-10 hexagonal board, ten hex cells to a side.
Hex is a strategy board game for two players played on a hexagonal grid, theoretically of any size and several possible shapes, but traditionally as an 11×11 rhombus.
 Players alternate placing markers or stones (Go stones make ideal playing pieces) on unoccupied spaces in an attempt to link their opposite sides of the board in an unbroken chain.
 One player must win; there are no draws.
 The game has deep strategy, sharp tactics and a profound mathematical underpinning related to the Brouwer fixed-point theorem.
 It was invented in the 1940s independently by two mathematicians, Piet Hein and John Nash.
 The game was first marketed as a board game in Denmark under the name Con-tac-tix, and Parker Brothers marketed a version of it in 1952 called Hex; they are no longer in production.
 Hex can also be played with paper and pencil on hexagonally ruled graph paper.