When attempting to capture a city, fortress, or other strongpoint, the formal rules of siege craft require the opposing force to ask the authorities if they would kindly surrender. The commanding officer of the garrison or civilian authorities would either accept a surrender and negotiate the terms or reject it. Upon a rejection, the siege would formally begin. While many sieges did not follow such strict rules of protocol, the epic siege of Vicksburg, Mississippi could said to have begun on May 18, 1862.
In May, U.S. Naval Commander Samuel Phillips Lee, cousin of Confederate General Robert E. Lee, proceed up the Mississippi River on the sloop-of-war USS Oneida. Upon arriving under a flag of truce, Lee formally delivered a request to Lazarus Lindsey, the mayor of Vicksburg, to surrender his city. Lee wrote
Mayor of the City of Vicksburg:
SIR: It becomes my duty to give you notice to remove the women and children beyond the range of our guns within twenty-four hours, as it will be impossible to attack the defenses without injuring or destroying the town, a proceeding which all the authorities of Vicksburg seem determined to require. I had hoped that the same spirit which induced the military authorities to retire from the city of New Orleans rather than wantonly sacrifice the lives and property of its inhabitants would have been followed here.
S. PHILLIPS LEE
Lindsey responded to Lee twenty-four hours later:
S. P. LEE, U. S. N.,
Commanding Advance of Naval Division:
...I will state that neither the municipal authorities nor the citizens will ever consent to the surrender of the city.
Confederate Lieutenant Colonel James Autrey, military governor of Vicksburg, was a bit more blunt in his rejection letter to Lee:
I have to state that Mississippians don't know and refuse to learn how to surrender to an enemy. If Commodore Farragut or Brigadier-General Butler can teach them, let them come and try.
Thus, Vicksburg would be no New Orleans. Upon getting the rejection, Farragut brought up more ships and shelled the city on May 27.