Born on 5 May 1945 in Ljubljana, he grew up as son of Ernest Aljancic Sr, a pioneer of ice hockey in Ljubljana, long-time national team player for Yugoslavia and IIHF Hall of Fame member. Ernest Aljancic Jr and his brother Jani followed him as ice hockey players. Ernest Aljancic, who also played football and handball in his younger years, spent 15 years with Olimpija Ljubljana and played six games for the Yugoslav national team.
Off the ice he was a lawyer and became known in Slovenia as a pioneer in sports marketing. He first worked in Slovenian ski and in 1994 he became Vice-President and in 1997 President of the Ice Hockey Federation of Slovenia – a position he held from 1997 until 2006 when he was named Honorary President. He came back for one season (2009/2010) when the federation was in financial difficulties before leaving his position for younger force. For several years he was also an executive committee member of the Olympic Committee of Slovenia.
Under his presidency the newly independent nation moved up the ranks and played in the top division of the IIHF Ice Hockey World Championship for the first time at the 2002 IIHF Ice Hockey World Championship where it participated in four out of five years between 2002 and 2006. During his time the lynx was adopted as symbol of the national team because these animals in the Slovenian forests are small but dangerous, the way the team should play against the big nations.
On the international stage Aljancic was an IIHF Council member between 2003 and 2012, having been elected in 2003 and re-elected in 2008 by the IIHF General Congress. In 2012 he was named Life Member. He had previously been active in IIHF committees starting with his appointment to the IIHF Marketing Committee in 1998.
Aljancic, also nicknamed “Nestl” in Slovenian hockey circles, continued to be involved in international ice hockey as chairman of tournament directorates in the IIHF Ice Hockey World Championship program until 2019 in particular in the Balkan region.