Modern warfare requires the delivery of secure, prompt and decisive action on the battlefield based on real-time high-speed data. Military communication systems rely mostly on secure HF communications via the ionosphere during warfare conditions, however, existing HF systems cannot provide such capability due to limited bandwidth and other ionospheric conditions limitations. Additionally, the public communications telecom infrastructure will most probably be incapacitated by hostile enemy operations during warfare. 5G-MILNET proposes the design of a novel portable 5G-based tactical communications bubble, which can be rapidly and dynamically deployed on demand in the battlefield, to enable seamless, resilient and secure, high-speed, real-time connectivity and data flow across the battlefield and local backend control and command operations. 5G-MILNET will be designed as a cost-effective solution offering significant tactical advantages to EU military forces, including high portability, privacy, security, resiliency against RF jamming, and robustness avoiding single points of failure. By establishing such a system, war fighters can achieve more effective operations in communications-contested and denied environments and have access to data to perform their missions anywhere in the world (assuming close proximity of up to a few kilometers between the Command and Control Center and the battlefield) without the use of pre-existing communications infrastructure. This will be achieved through the use of small size 5G Software Defined Radio (SDR) micro cells that can be carried out by personnel as well as by military vehicles in the battlefield area. The high-speed backhaul links with the headquarters can be established by the deployment of airborne 5G SDR units carried by a series of lightweight (graphene based) purpose-designed low altitude drones operated (semi) autonomously through swarm intelligence in strategic positions along the path.