WERE tendencies in the direction of regional difference in the later Russian Empire outweighing tendencies in the direction of homogeneity? In view of the fact that the empire fell apart in 1917, it looks as if the emphasis ought to be on difference. A good case, however, can also be made for homogeneity. I shall therefore be proposing that the regions of the Russian Empire occupied a more or less constant position on an imaginary `divergence–coalescence spectrum'. Admittedly, the contest between divergence and coalescence ceased to be equal during the First World War and the empire collapsed. This imbalance, however, turned out to be temporary. The empire re-emerged under a new name at the end of 1922 and for sixty-nine years thereafter occupied more or less the same place on the divergence–coalescence spectrum that it had occupied before it collapsed. So I shall be arguing that, except under extreme duress, the empire was stable. It is this stability I wish to draw to your attention. One's natural inclination is to think of the later Russian Empire as a hotbed of change. I have argued in a recent article that the inclination should be resisted in analyses of work-patterns. I shall argue today that it should also be resisted in the field of regional diversity. To make the case, I shall divide what I have to say into three parts, the first on divergence, the second on coalescence and the third on the First World War.