Adequately covering the topic of energy-efficiency in Europe and Japan in the 20th century requires more time and skills than the author has available. So the author is asking for help. While the results will likely be somewhat similar to that for the U.S., there will likely be some significant differences. Many countries and languages are involved. This research can best be done by people who know the languages and have access to the transportation literature of each country. Any volunteers?
The first major part of this article has covered the energy-efficiency of travel for the United States (U.S.). The situation in Europe was likely somewhat similar, only the rise of the automobile came much later. Public transportation (rail and bus) dominated passenger travel long after the U.S. had opted for the automobile.
In the U.S. and Canada, the modal shifts to the auto happened in most parts of the countries in a roughly homogeneous fashion. In all the states of the U.S., the automobile became dominant in the 1920s. But the rise of the automobile in Europe (and elsewhere) not only happened much later, it was a different story in each country and there were very wide differences between countries.
For example, in the Soviet Union, public transport was dominant (see USSR modal split. In 1970, only 2.8% of pass-km was by private automobile. But in 1970 Western Europe, automobile transportation dominated with automobile pass-km being about 75% (See Europe) of the total.
Today, the automobile is very dominant in Western Europe with a modal share of 85% of land transportation in 1999 (See Europe). But rapid automobilisation, like the U.S. in the 1920s, didn't happen in Western Europe until about 35 years after it happened in the U.S. In the 1920s, the U.S. was awash in oil and autos were mass produced. But not so in Western Europe. Only the wealthy there could afford autos in most cases. Then came the great depression in the 1930s and World War in the 1940s. During all this time, most Europeans were transported by railroads and buses (and not autos). Some used bicycles. It wasn't until about 1970 that there was about 1 auto for every 5 people, the same as for the U.S. by 1930.
So the automobilisation of Western Europe during 1955-1970, in contrast to the U.S. in the 1920s, didn't increase energy-efficiency since most Western Europe railroads were already efficient diesel or electric. It was a shift from a more energy-efficient rail mode to a less efficient automobile mode.
Today in Western Europe, the automobile is the dominant mode of travel, as it is in the U.S. But there is still several times more rail and bus travel than in the U.S. See Europe.
In Japan, rail was the major mode of travel until about 1975. In 1960 there was 4 times as much travel by railroad than by automobile. Previous to 1960 there was even less travel by auto. See Japan. But by 2000, 27% of travel in Japan was by rail as compared to only about 6% in Europe and a little over 1/2 % in the U.S.. So in Japan rail's share is about the same as it was in the U.S. during World War II (30%). See [Trans in Am.]
Also, rail travel in Japan is a few times more energy-efficient than in the U.S., likely due to higher load factors, more seats per unit weight, and the higher efficiency of electric trains with regenerative braking. Since Japan is relatively small, most rail trips do not require sleeping cars, results in less train weight per passenger. See Japan. In Japan, most all passenger traffic goes over electrified rail lines.
So for Japan, rail travel after 1965 continued to slowly grow but automobile travel grew much faster. As a result, the average energy efficiency of travel dropped due to the shift in percentage shares from rail and bus (highly efficient modes in Japan) to the automobile and airplane (lower efficient modes in Japan). The modal shift in the U.S. happened much earlier in the steam railroad era (low efficiency trains) so that average energy efficiency increased while this was happening in the U.S. For Japan, energy efficiency did increase during the period of conversion from steam to electric, starting in the 1930's.