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In this paper we analyze the kinematics, chemistry, and physical propertiesof a sample of the most metal-poor damped Lyman-alpha systems (DLAs), touncover their links to modern-day galaxies. We present evidence that the DLApopulation as a whole exhibits a `knee' in the relative abundances of thealpha-capture and Fe-peak elements when the metallicity is [Fe/H] ~ -2.0,assuming that Zn traces the build-up of Fe-peak elements. In this respect, thechemical evolution of DLAs is clearly different from that experienced by MilkyWay halo stars, but resembles that of dwarf spheroidal galaxies in the LocalGroup. We also find a close correspondence between the kinematics of LocalGroup dwarf galaxies and of high redshift metal-poor DLAs, which furtherstrengthens this connection. On the basis of such similarities, we propose thatthe most metal-poor DLAs provide us with a unique opportunity to directly studythe dwarf galaxy population more than ten billion years in the past, at a timewhen many dwarf galaxies were forming the bulk of their stars. To this end, wehave measured some of the key physical properties of the DLA gas, includingtheir neutral gas mass, size, kinetic temperature, density, and turbulence. Wefind that metal-poor DLAs contain a warm neutral medium with T_gas ~ 9600 Kpredominantly held up by thermal pressure. Furthermore, all of the DLAs in oursample exhibit a subsonic turbulent Mach number, implying that the gasdistribution is largely smooth. These results are among the first empiricaldescriptions of the environments where the first few generations of stars mayhave formed in the Universe.

The most metal-poor damped Lyman alpha systems: An insight into dwarf galaxies at high redshift