[2][11][12] Christian's early research interests focused on the history of Russia and the Soviet Union, with particular emphases on the Russian peasantry, including their diet and the role of vodka in their lives.
In 1984, he co-wrote, along with R. E. F. Smith, a history about the Russian peasantry entitled Bread and Salt that showed, among other things, how such foods along with dairy products were used as seasonings.
[11] During the 1980s, he read widely and began a program to describe human history in the context of very large time scales from cosmology and astronomy, covering the almost fourteen billion years since the Big Bang.
[14] It was a novel approach that emphasizes summary findings from biology, cosmology, astronomy, geology, and anthropology to show what happened before homo sapiens became prevalent on the Earth.
[11][9] In 2010, Christian predicted that historical scholarship would have less emphasis on document-based research and more on empirical research, and he wrote:[11][16] ...Over the next fifty years we will see a return of the ancient tradition of "universal history"; but this will be a new form of universal history that is global in its practice and scientific in its spirit and methods.Philanthropist Bill Gates presented David Christian at the TED 2011 Conference in Long Beach, California.
At that time, Christian announced his Big History Project initiative to teach the subject to secondary school students in Australia and the United States.