Carnival 

Carnival Week is the Week leading up to Ash Wednesday culminating in the festivities on the day before Ash Wednesday (Fat Tuesday), Many begin the real celebrating on the Sunday before Ash Wednesday. 

Shrove Monday, also known as Carnival Monday, Collop Monday, Fat Monday, Hall Monday, Merry Monday, or Rose Monday, is the Monday before Ash Wednesday every year. It the second to last day of Carnival or Shrovetide celebrations of the week before Lent, it precedes Shrove Tuesday (Fat Tuesday).

Fat Tuesday, also commonly known as Mardi Gras or Pancake Tuesday, is the last and most celebrated day of Carnival. It is the Day before Ash Wednesday and 47 days before Easter Sunday. It will be obeserved on...

The final day of Carnival, celebrated by Catholics worldwide,  is usually known as Fat Tuesday, Shrove Tuesday, or Mardi Gras but is also known as... 
Pancake Day or Shrove Tuesday in England
Sprengidagur or Bursting Day in Iceland
Užgavėnės in Lithuania
Fettisdagen in Sweden
Laskiainen in Finland

Mardi Gras 

The first parade to have floats was at Mardi Gras in New Orleans, Louisiana in 1868. The Mardi Gras colors of purple, green and gold were selected by Grand Duke Alexis Alexandrovitch Romanoff of Russia during a visit to New Orleans in 1872. Purple stands for justice, gold stands for power and green stands for faith. The earliest reference to Mardi Gras "Carnival" appears in a 1781 report to the Spanish colonial governing body. That year, the Perseverance Benevolent & Mutual Aid Association is the first of hundreds of clubs and carnival organizations formed in New Orleans. 

Mardi Gras (New Orleans) Timeline

In 1699 A French-Canadian explorer, Jean Baptiste Le Moyne Sieur de Bienville, claimed a plot of ground 60 miles directly south of New Orleans and called it "Pointe due Mardi Gras." He also established "Fort Louis de la Louisiane" (which is now Mobile) in 1702.
In 1703, the tiny settlement of Fort Louis de la Mobile celebrated the very first Mardi Gras.
In 1704, Mobile established a secret society, the Masque de la Mobile.
The Masque de la Mobile lasted until 1709.
In 1710, the "Boeuf Graf Society" was formed and paraded from 1711 through 1861. The procession led by a huge bull's head pushed alone on wheels by 16 men. This always occurred on Fat Tuesday.
In 1856, the "Mystick Krewe of Comus" was organized to observe the Mardi Gras in a less crude fashion.
In 1871, the Mardi Gras's second "Krewe" was formed, the Twelfth Night Reveler's, this is the first account of Mardi Gras "throws."
In 1872, a group of businessmen invented a King of Carnival (Rex) to parade in the first daytime parade. They introduced the Mardi Gras colors of purple, green and gold, the Mardi Gras song, and the Mardi Gras flag.
In 1873, the first floats were constructed entirely in New Orleans instead of France.
In 1875, Governor Warmoth of Louisiana signs the "Mardi Gras Act" making it a legal holiday in Louisiana, which it still is.
In 1918 and 1919 Mardi Gras was canceled when the United States was fighting in the First World War.
In the 1920's and 1930's the celebration struggled through Prohibition and The Great Depression.
In the 1940' Mardi Gras prospered, although it was canceled during the war years.

 Rio Carnival

parties, festivals and glamorous balls.  

The Rio Carnival 2013 is from February 8th until February 12th
The Rio Carnival 2014 is from February 28th until March 4th
The Rio Carnival 2015 is from February 13th until February 17th
The Rio Carnival 2016 is from February 5th until February 9th
The Rio Carnival 2017 is from February 24th until February 28th
The Rio Carnival 2018 is from February 9th until February 13th
The Rio Carnival 2019 is from March 1st until March 5th
The Rio Carnival 2020 is from February 21st until February 25th
The Rio Carnival 2021 is from February 12th until February 16th
The Rio Carnival 2022 is from February 25th until March 1st
The Rio Carnival 2023 is from February 17th until February 21st
The Rio Carnival 2024 is from February 9th until February 13th
The Rio Carnival 2025 is from February 28th until March 4th
The Rio Carnival 2026 is from February 13th until February 17th
The Rio Carnival 2027 is from February 5th until February 9th
The Rio Carnival 2028 is from February 25th until February 29th
The Rio Carnival 2029 is from February 9th until February 13th
The Rio Carnival 2030 is from March 1st until March 5th

Carnival Festivals and Observations