Synchrony or diatopy means 3D space with simultaneous events in order of increasing time. Space-time is synchronic or diatopic.
Diachrony means 3D time with simulocuous events in order of decreasing distance. Time-space is diachronic.
Chronicles and histories are diachronic. Models and theories are synchronic or diatopic.
Knowledge of the distances between objects is important in order to understand their motions. Knowledge of the modal durations between subjects is important in order to understand their movements. In history travel time matters more than travel distance. In science travel distance matters more than travel time.
For the study of history, 3D time is more significant then 3D space. What matters more is not the distance between places, but the transit time. The reason is that time is the measure of effort to go from one place to another.
Historical events such as military campaigns are often shown in maps. Although these maps contain the geography, what matters is the time scale or time of events, which is often highlighted. For example, this map of the Battle of Waterloo:
Or for ancient history consider these travel time maps to and from Rome:
Time is to history as space is to science.