Oettinger cut his teeth in European politics with the energy portfolio at the outgoing Commission, gaining a reputation as well-versed in his subject despite initial scepticism about his appointment.
The 60-year-old, who was appointed Digital Economy and Society Commissioner in European Commissioner Jean-Claude Juncker's new team on Wednesday, took his place at the table in Brussels four years ago.
He was nominated almost by chance out of tactical political reasons after fellow conservative Chancellor Angela Merkel's two other favourites for the job turned it down.
At the time, the trained lawyer and economist was premier of the prosperous southwestern state of Baden-Württemberg and had just put in an unimpressive performance in the 2009 parliamentary election.
His reputation was under a cloud after he gave a speech praising former Baden-Württemberg premier Hans Filbinger, a military judge in the German navy during the Nazi period, as an opponent of Nazism.
All this plus his inexperience of European politics made the Brussels appointment a surprise to many. His language skills for working in his new international environment initially drew ridicule.
A faltering command of English delivered in a heavy Swabian regional accent led to one of his first speeches in English making a splash on YouTube with nearly 700,000 hits.
However, Oettinger quickly brushed up his English and lost no time in diving into his new job as Energy Commissioner, soon able to talk inexhaustibly about high-tension electricity lines and gas reserves.
The divorced father-of-one, who has been dating event manager Friederike Beyer since 2008, became a sought-after speaker and is credited with developing the portfolio from something of a sideshow to a central facet of European policy.
His most impressive achievements came in the final months of his mandate thanks to his determination in trying to mediate a resolution to a bitter gas supply dispute between Ukraine and Russia.
Although an accord remains elusive, the German has managed to bring the two sides repeatedly to the table for discussions amid fighting in the ex-Soviet satellite state that sparked the worst East-West standoff since the Cold War.
After Japan's Fukushima nuclear disaster in 2011, he introduced stress tests for European nuclear power stations, straying into territory normally strictly reserved for member states to oversee.
He has a track record for being able to take some distance from German domestic interests, observers say, in criticizing, for example, Germany's system of subsidies for renewable forms of energy.
But critics accuse him of having sided with the energy industry, while environmentalists say he often failed to follow up words with actions. Greens in the European Parliament call him an “anti-modernizer,” despite his background in a CDU-Greens coalition in his home state before working in Brussels.
His ability to shine in less prominent roles will serve him well in his new job, which has a smaller area of responsibility and will see him under the supervision of Estonian Commission Vice-President Andrus Ansip.
Important areas of work will be breaking down national barriers, especially roaming costs for smartphone users, as well as modernizing European copyright law, simplifying the process of starting a company and improving the continent's online security.
Oettinger has said that he is “happy” and motivated” with his new post.
No digital native himself, Oettinger joked that his 16-year-old son “would become my honorary adviser, I expect,” when challenged on his knowledge of the new job. The new digital economy commissioner is an occasional Tweeter.