  Cosmic strings, if they exist, source nonlinear and non-Gaussian
perturbations all the way back to the time of equal matter and radiation (and
earlier). Here, we compute the mass function of halos seeded by a scaling
distribution of cosmic string loops, and we compare the results with the
predictions of the standard Gaussian $\Lambda$CDM model. Assuming a simple
linear relation between stellar mass and halo mass, we also compute the stellar
mass function. The contribution of cosmic strings dominates at sufficiently
high redshifts $z > z_c$ where $z_c$ depends on the mass of the halo and on the
mass per unit length $\mu$ of the strings and is of the order $z_c \sim 12$ for
$G\mu = 10^{-8}$. We find that strings with this value of $G\mu$ can explain
the preliminary JWST data on the high redshift stellar mass density. Based on
an extreme value statistic, we find that the mass of the heaviest expected
string-seeded galaxy for the current JWST sky coverage is compatible with the
heaviest detected galaxy. Given the uncertainties in the interpretation of the
JWST data, we discuss predictions for higher redshift observations.
