split-window-keep-point

split-window-keep-point is a variable defined in `window.el'.
Its value is

t

Documentation:
If non-nil, C-x 2 preserves point in the new window.
If nil, adjust point in the two windows to minimize redisplay.
This option applies only to `split-window-below' and functions
that call it. The low-level `split-window' function always keeps
the original point in both windows.

You can customize this variable.