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Ceramics represent a crucial branch of materials science and have been utilized since the dawn of human civilization. Due to their unique bonding nature, ceramics often surpass metals and polymers in applications that demand high modulus, chemical resistance, thermal stability, and corrosion resistance. On average, ceramics are frequently exposed to harsh conditions to meet the continuous demands posed by humankind in applications requiring energy generation, energy storage, or as catalysts in chemical synthesis, necessitating improved material design through composition optimization. The incorporation of minor quantities of elements into ceramics can enhance their properties, analogous to alloying in metals, leading to the development of advanced technical ceramics such as Y-stabilized ZrO₂ and YBCO. Further improvement of properties is possible by increasing the number of constituent elements, approaching an equimolar ratio, which increases the configurational entropy. A sufficiently high amount of configuration entropy can stabilize compositions, overcoming enthalpy effects. Such ceramics are named compositionally complex ceramics due to their unique thermodynamic stability and possess tailorable functional properties that may vary as a function of composition. Although compositionally complex ceramics represent an interesting class of ceramics, the issue of inhomogeneity often hinders the synthesis of such ceramics. Conventional solid-state techniques offer a straightforward route to synthesizing such ceramics, but require high firing temperatures to facilitate solid-state diffusion. Additionally, solid-state techniques can constrain the geometry of the fabricated ceramic and also limit the compositions that can be used. Wet-chemical methods offer viable alternatives, ensuring molecular-level homogeneity and thereby reducing the firing temperature, especially for non-oxidic ceramics such as nitrides and carbides; however, the synthesis procedures for nitrides remain relatively unexplored. In this dissertation, a non-oxidic sol-gel route is adapted for the synthesis of compositionally complex carbide and nitride ceramic powders. The method involves the double ammonolysis of a metal dimethylamido xerogel, obtained through the crosslinking of a dimethylamido mixture with liquefied ammonia, ensuring minimal contamination by carbon and oxygen under ideal conditions. Detailed structural investigations were conducted to elucidate the structure, local ordering, and the crystallite size of the obtained nitrides. The electrocatalytic properties of the nitrides were investigated for electrocatalytic nitrogen reduction, along with their carbide counterparts, synthesized through a polymeric route involving the chelation of metals with dibenzoylmethane. For the oxide ceramics, a solvent-deficient mechanochemical synthesis route was developed, involving the mixing of hydrated salts with alkali, thereby eliminating the need for external solvents, while ensuring homogeneity. The resulting oxides were characterized using synchrotron-based techniques to determine oxidation states and cation distribution. Overall, this dissertation presents novel synthesis strategies for compositionally complex ceramics, providing insights into their structure and functional properties, and demonstrating their potential for advanced applications.