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Many aspects concerning the formation of spiral and disc galaxies remainunresolved, despite their discovery and detailed study over the past $150$years. As such, we present the results of an observational search forproto-spiral galaxies and their earliest formation, including the discovery ofa significant population of spiral-like and clumpy galaxies at $z>1$ in deep\textit{Hubble Space Telescope} CANDELS imaging. We carry out a detailedanalysis of this population, characterising their number density evolution,masses, star formation rates and sizes. Overall, we find a surprisingly highoverall number density of massive $M_{*} >10^{10}\mathrm{M}_{\odot}$spiral-like galaxies (including clumpy spirals) at $z > 1$ of $0.18\,{\rmper}\, \mathrm{arcmin}^{-2}$. We measure and characterise the decline in thenumber of these systems at higher redshift using simulations to correct forredshift effects in identifications, finding that the true fraction ofspiral-like galaxies grows at lower redshifts as $\sim$ $(1+z)^{-1.1}$. This issuch that the absolute numbers of spirals increases by a factor of $\sim 10$between $z = 2.5$ and $z = 0.5$. We also demonstrate that these spiral-likesystems have large sizes at $z>2$, and high star formation rates, above themain-sequence, These galaxies represent a major mode of galaxy formation in theearly universe, perhaps driven by the spiral structure itself. We finallydiscuss the origin of these systems, including their likely formation throughgas accretion and minor mergers, but conclude that major mergers are anunlikely cause.

Observations of the Initial Formation and Evolution of Spiral galaxies at $1 < z < 3$ in the CANDELS fields