‘Cliodynamics’ is a transdisciplinary area of research integrating historical macrosociology, economic history/cliometrics, mathematical modeling of long-term social processes, and the construction and analysis of historical databases.
Here is a Wikipedia page for Peter Turchin, the journal's editor, and his welcome to the new journal. I had previously linked to a paper by Turchin and Scheidel about a possible link between coin hoard size and population.
Cliodynamics (from the muse Clio, traditionally associated with history) is certainly an interesting concept, which I might summarize as quantitative history. Here are some paper titles from the journal's inaugural issue to give you an idea of what it's supposed to be about:
A Dynamic Theory of Battle Victory and Defeat
Synthezing Secular, Demographic-Structural, Climate and Leadership Long Cycles: Moving Toward Explaining Domestic and World Politics in the Last Millennium
Thompson, William R
Cycling in the Complexity of Early Societies
Gavrilets, Sergey, Anderson, David G, Turchin, Peter
Why Has the Number of International Non-Governmental Organizations Exploded since 1960?
Turner, Edward A L
New Patterns in Global History: A Review Essay on Strange Parallels by Victor Lieberman
Goldstone, Jack A
The Silk Road: A Review Essay on Empires of the Silk Road by Christopher I. Beckwith
Hall, Thomas D
Tests in Time: A Review of Natural Experiments of History, edited by Jared Diamond and James A. Robinson
Currie, Thomas E
Accumulation of Knowledge in Theoretical History: A Review Essay on Historical Macrosociology by Nikolai S. Rozov
Tsirel, Sergey V
Regularities in Human Actions: A Review of Bursts by Albert-László Barabási
Zeng, An, Roehner, Bertrand
An interesting set of topics for sure!