  We formulate the nonlinear isovector model in a curved background, and
calculate the spherically symmetric solutions for weak and strong coupling
regimes. The usual belief that gravity does not have appreciable effects on the
structure of solitons will be examined, in the framework of the calculated
solutions, by comparing the flat-space and curved-space solutions. It turns out
that in the strong coupling regime, gravity has essential effects on the
solutions. Masses of the self-gravitating solitons are calculated numerically
using the Tolman expression, and its behavior as a function of the coupling
constant of the model is studied.
