  We present the clump populations detected in 18 lensed galaxies at redshifts
1 to 8.5 within the lensing cluster field SMACS0723. The recent JWST Early
Release Observations of this poorly known region of the sky have revealed
numerous point-like sources within and surrounding their host galaxies,
undetected in the shallower HST images. We use JWST multiband photometry and
the lensing model of this galaxy cluster to estimate the intrinsic sizes and
magnitudes of the stellar clumps. We derive optical restframe effective radii
from $<$10 to 100s pc and masses ranging from $\sim10^5$ to $10^9$ M$_{\odot}$,
overlapping with massive star clusters in the local universe. The ages range
from 1 Myr to 1 Gyr. We compare the crossing time to the age of the clumps and
determine that between 45 and 60 % of the detected clumps are consistent with
being gravitationally bound. The lack of Gyr old clumps suggest that the
dissolution time scales are shorter than 1 Gyr. We see a significant increase
in the luminosity (mass) surface density of the clumps with redshift. Clumps in
galaxies at the reionisation era have stellar densities higher than massive
clusters in the local universe. We zoom-in into single galaxies at redshift
$<6$ and find for two galaxies, the Sparkler and the Firework, that their star
clusters/clumps show distinctive colour distributions and location surrounding
their host galaxy that are compatible with being accredited or formed during
merger events. The ages of some of the compact clusters are between 1 and 4
Gyr, e.g., globular cluster precursors formed around 9-12 Gyr ago. Our study,
conducted on a small sample of galaxies, shows the potential of JWST
observations for understanding the conditions under which star clusters form in
rapidly evolving galaxies.
