The Second Battle of Rivas occurred on 11 April 1856 between Costa Rican militia under General Mora and the Nicaraguan forces of William Walker. The lesser known First Battle of Rivas took place on 29 June 1855 between Walker's forces and the forces of the Chamorro government of Nicaragua.

At the time, a major trade route between New York City and San Francisco ran through southern Nicaragua. Ships from New York would enter the San Juan River from the Atlantic and sail across Lake Nicaragua. People and goods would then be transported by stagecoach over a narrow strip of land near the city of Rivas, before reaching the Pacific and being shipped to San Francisco. The commercial exploitation of this route had been attained from a previous Nicaraguan administration to Wall Street tycoon Cornelius Vanderbilt's Accessory Transit Company. Garrison and Morgan had wrested control of the company from Vanderbilt and then supported Walker's expedition. Vanderbilt spread rumors that the company was issuing stock illegally in order to depress its value, allowing him to regain controlling interest.

Great Lent, or the Great Fast, is the most important fasting season in the church year in Eastern Christianity, which prepares Christians for the greatest feast of the church year, Pascha (Easter). In many ways Great Lent is similar to Lent in Western Christianity. There are some differences in the timing of Lent (besides calculating the date of Easter) and how it is practiced, both liturgically in the public worship of the church and individually.

One difference between Eastern Christianity and Western Christianity is the calculation of the date of Easter (see Computus). Most years, the Eastern Pascha falls after the Western Easter, and it may be as much as five weeks later; occasionally, the two dates coincide. Like Western Lent, Great Lent itself lasts for forty days, but unlike the West, Sundays are included in the count. Great Lent officially begins on Clean Monday, seven weeks before Pascha (Ash Wednesday is not observed in Eastern Christianity) and runs for 40 contiguous days, concluding with the Presanctified Liturgy on Friday of the Sixth Week. The next day is called Lazarus Saturday, the day before Palm Sunday. However, fasting continues throughout the following week, known as Passion Week or Holy Week, and does not end until after the Paschal Vigil early in the morning of Pascha (Easter Sunday).