Brutus has calmed himself after a turbulent time and he is fully awake when the ghost manifests. The dying flame of his lamp announces the ghost's presence.
A soldier is one who fights as part of a land-based army. A soldier can be an enlisted person, a non-commissioned officer, or an officer in the army.
A veteran is one who has served in the armed forces, especially one who has served in combat. The National Guard and Reserve is included. It is especially applied to those who served for an entire career, usually of 20 years or more, but may be applied for someone who has only served one tour of duty.