what are some events that led to the collapse of reconstruction in the south?

Check these sites.

http://wps.ablongman.com/long_carnes_an_11/0,7137,251530-,00.html

http://encarta.msn.com/encyclopedia_761556642_2/Reconstruction_(U_S_history).html

http://www.sparknotes.com/history/american/reconstruction/summary.html

Since this is not my area of expertise, I searched Google under the key words "Southern reconstruction collapse" to get these possible sources:

http://www.historycooperative.org/journals/ht/39.3/br_11.html
http://www.vanderbilt.edu/AnS/history/carltodl/277/endrecon.htm
http://books.google.com/books?id=-tsir90xfo4C&pg=PA473&lpg=PA473&dq=southern+reconstruction+collapse&source=web&ots=y9Iy5fMSwm&sig=xjYsAhyzaACFhDxs15sqdJXbt7w#PPA472,M1
http://www.civilwarhome.com/reconstruction.htm
(Broken Link Removed)

In the future, you can find the information you desire more quickly, if you use appropriate key words to do your own search.

I hope this helps. Thanks forasking.

Your question is a bit one-sided. Historians today are still arguing about whether Reconstruction was a failure. Reconstruction certainly had its bad sides as well as ending peacefully with the Southern states fully reuniting with the Union in a period of about 12 years from 1865 until 1877.

Nevertheless I will attempt to give you the side that you wanted and neglect the other side for now.

Lincoln's death had a proofing effect upon Reconstruction even though on the face of it Johnson's plan was very similar. The problem was that Andrew Johnson was not a Lincoln. Johnson did not have a college education. In fact he did not learn to read until he was older. He was a southerner and a former slave owner. It is generally believed that Lincoln could control the Radical Republicans while Johnson could not. Johnson began his term of President after Lincoln was assassinated and he was already hated by the Radical Republicans. Southern states passed laws that were known as the Black Codes. These laws provided among other things that the penalty for interracial marriage was death, Blacks could not testify in court against whites, that Blacks could only live in certain areas. Even hough Johnson attempted to stop all federal laws assisting the blacks they were overridden by Congress since the Southern states had no votes in Congress.

"Although Reconstruction did protect some of the political and
civil rights of the Afro-American community, it achieved almost
nothing in improving the social and economic situation. The
concept of social and economic rights was almost nonexistent a
century ago. Political rights, however, without economic security
could be a mere abstraction. Meaningful freedom had to be more
than the freedom to starve. This meant that the ex-slave needed
land, tools, and training to provide him with an economic base
that would make his freedom real. The ex-slave had limited
education, limited experience, a servile slave attitude, and he
was in need of social and economic training to compensate for the
years of slavery. Without this he could not enter a competitive
society as an equal. Emancipation was not enough."
Source http://www.rit.edu/~nrcgsh/BX/bx06b.html

"Reconstruction failed. Even though Reconstruction failed, at least we tried but
some people have to learn how to change. Reconstruction changed the way of life
for blacks. Some changes were good and some changes made life difficult, but
overall the blacks made it out of slavery safely. Reconstruction was the
original beginning of the Civil Rights Act. The fact that African-Americans had
made it so far gave them the strength to keep going and fight for what they
believe in." Source http://www.thehistoryconnection.com/Reconstruction-Failure.html

Also read http://www.colorado.edu/AmStudies/lewis/2010/failure.htm

The collapse of Reconstruction in the South was influenced by several significant events. Understanding these events can help provide insights into why Reconstruction ultimately failed. Here are some key factors:

1. Presidential Reconstruction: Following the end of the Civil War, President Andrew Johnson implemented lenient policies that allowed former Confederate states to reenter the Union without significant consequences. This approach undermined the efforts to secure equal rights for newly freed African Americans.

2. Black Codes and Jim Crow Laws: Southern states enacted a series of laws known as Black Codes, which aimed to limit the rights and freedoms of African Americans. These laws, later reinforced by the introduction of Jim Crow laws, created a segregated society that perpetuated racial discrimination and inequality.

3. Ku Klux Klan and White Supremacy: The emergence of white supremacist groups, such as the Ku Klux Klan, played a pivotal role in promoting and enforcing racial terror. These groups intimidated, attacked, and murdered African Americans, as well as white Republicans who supported Reconstruction.

4. Violence and Intimidation: Acts of violence, including riots and massacres, were widespread during this period. For instance, the Colfax Massacre in Louisiana (1873) resulted in the deaths of over 150 African American men. Such incidents weakened the resolve of the federal government to enforce Reconstruction policies.

5. Election of 1876 and Compromise of 1877: The 1876 presidential election between Rutherford B. Hayes and Samuel Tilden ended with an electoral dispute. To resolve the deadlock, a political compromise was reached. As a result, federal troops were withdrawn from the South, signaling the end of Reconstruction. Southern Democrats regained control, and racial segregation was solidified.

Understanding the events that led to the collapse of Reconstruction involves examining historical documents, records, and scholarly research. Accessing academic books, articles, or reputable online resources can provide a comprehensive understanding of this complex period in American history.