The construction or repair of concrete infrastructure involves the placement of fresh, workable concrete made of water, cement and aggregates, which subsequently gains its strength and durability through microstructure development accompanied by solidification. The fluid-to-solid transition as the result of the complex reactions of the cement with the water, i.e., hydration, has been the focus of cement research since its early years. However, the precise and accurate prediction of this process remains challenging and established models most often rely on strong simplifications or require high computational or experimental efforts. Here we present a new approach for the prediction of the early hydration process and the fluid-to-solid transition by applying thermodynamic modeling and simulation as input to a multi-scale material model. The application of in-situ quantitative X-ray diffraction for implementation of cement dissolution within the thermodynamic simulation is shown to be more accurate with regard to dissolution description and simulation results compared to the widely adapted modified Parrot & Killoh model. The mechanical properties of hydrating cement paste is derived by upscaling the microscopic properties using multi-level continuum micromechanics based homogenization schemes. Model predictions are compared with experimental measurements. A sensitivity analysis is performed to gain insight into the role of the microstructure quantifiers on the macroscopic properties. The results show, how early cement paste development can be derived by application of low-cost experimental and computational methods enabling accurate prediction of chemical phase alterations and microstructural development. Following the proposed approach, it is possible to investigate state-of-.the-art questions of cement hydration including the influence of individual hydrate phases on the solidification process.