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DOI: 10.1002/adom.202000101 through most material systems. These unique properties of terahertz waves have been exploited for both fundamental sciences and advanced applications, alike. However, these properties have also been a bane and has significantly hindered the development of efficient terahertz technologies. However, in recent years, research effort in terahertz technologies has been accelerated from both electronics as well as photonics communities, owing to its immense potential, especially in high-speed wireless communication, non-destructive imaging, high resolution spectroscopy, and for probing of ultrafast field driven as well as ultrastrong energy coupled processes.[1–8] One of the major challenges in the manipulation of terahertz waves is its minimal interaction with naturally occurring materials. Hence, cavity based resonant terahertz interaction has been widely explored using metamaterials.[9–12] Metamaterials are artificially patterned sub-wavelength structures, whose optical properties are predominantly determined by the pattern geometry. Hence, metamaterials are topographically flat, functionally versatile, and highly scalable. Furthermore, integration of dynamic materials or structurally reconfigurable microstructures within metamaterial resonators allow for on-demand Spatiotemporal manipulation of electromagnetic waves has recently enabled a plethora of exotic optical functionalities, such as non-reciprocity, dynamic wavefront control, unidirectional transmission, linear frequency conversion, and electromagnetic Doppler cloak. Here, an additional dimension is introduced for advanced manipulation of terahertz waves in the space-time, and frequency domains through integration of spatially reconfigurable microelectromechanical systems and photoresponsive material into metamaterials. A large and continuous frequency agility is achieved through movable microcantilevers. The ultrafast resonance modulation occurs upon photoexcitation of ion-irradiated silicon substrate that hosts the microcantilever metamaterial. The fabricated metamaterial switches in 400 ps and provides large spectral tunability of 250 GHz with 100% resonance modulation at each frequency. The integration of perfectly complementing technologies of microelectromechanical systems, femtosecond optical control and ion-irradiated silicon provides unprecedented concurrent control over space, time, and frequency response of metamaterial for designing frequency-agile spatiotemporal modulators, active beamforming, and low-power frequency converters for the next generation terahertz wireless communications.