Some context: The Mississippian culture was a mound-building Native American civilization archeologists date from approximately 800 CE to 1600 CE, varying regionally. It was composed of a series of urban settlements and satellite villages (suburbs) linked together by a loose trading network, the largest city being Cahokia, believed to be a major religious center. The civilization flourished from the southern shores of the Great Lakes at Western New York and Western Pennsylvania in what is now the Eastern Midwest, extending south-southwest into the lower Mississippi Valley and wrapping easterly around the southern foot of the Appalachians barrier range into what is now the Southeastern United States. The Mississippian way of life began to develop in the Mississippi River Valley (for which it is named).
The Mississippi stage is usually divided into three or more chronological periods. Each period is an arbitrary historical distinction varying regionally. At a particular site, each period may be considered to begin earlier or later, depending on the speed of adoption or development of given Mississippian traits. The "Mississippi period" should not be confused with the "Mississippian culture". The Mississippi period is the chronological stage, while Mississippian culture refers to the cultural similarities that characterize this society.  The Early Mississippi period (c. 1000-1200 CE) had just transitioned from the Late Woodland period way of life (500-1000). Different groups abandoned tribal lifeways for increasing complexity, sedentism, centralization, and agriculture. Production of surplus corn and attractions of the regional chiefdoms led to rapid population concentrations in major centers.  The Middle Mississippi period (c. 1200-1400) is the apex of the Mississippi era. The expansion of the great metropolis and ceremonial complex at Cahokia (in present-day Illinois), the formation of other complex chiefdoms, and the spread and development of SECC art and symbolism are characteristic changes of this period. The Mississippian traits listed above came to be widespread throughout the region.  The Late Mississippi period (c. 1400-1540) is characterized by increasing warfare, political turmoil, and population movement. The population of Cahokia dispersed early in this period (1350-1400), perhaps migrating to other rising political centers. More defensive structures are often seen at sites, and sometimes a decline in mound-building and large scale, public ceremonialism. Although some areas continued an essentially Middle Mississippian culture until the first significant contact with Europeans, the population of most areas had dispersed or were experiencing severe social stress by 1500. Along with the contemporaneous Ancestral Pueblo peoples, these cultural collapses coincide with the global climate change of the Little Ice Age. Scholars theorize drought and the reduction of maize agriculture, together with possible deforestation and overhunting by the concentrated populations, forced them to move away from major sites. This period ended with European contact in the 16th century.
Are there any other interesting aspects about this article?
A: The "Mississippi period" should not be confused with the "Mississippian culture".

Some context: Mellencamp is of German ancestry. He was born with spina bifida, for which he had corrective surgery as an infant. Mellencamp formed his first band, Crepe Soul, at the age of 14 and later played in the local bands Trash, Snakepit Banana Barn and the Mason Brothers. When Mellencamp was 18, he eloped with his pregnant girlfriend Priscilla Esterline.
Country music star Keith Urban has consistently cited Mellencamp's influence on his music. It originated when Mellencamp's Lonesome Jubilee tour went to Australia in 1988; Urban was in attendance at one of the concerts and described the experience as an "epiphany."  "'I Need A Lover' and 'Hurts So Good' were massive hits in Australia", Urban told the Vancouver Sun in 2016. "I played so many of those songs in my cover bands. But for me, The Lonesome Jubilee was the defining record and tour. I've since gotten to know John a little bit and it was one of the greatest opportunities I've ever had to meet a hero and tell him about a concert you went to when you were a nobody and how much of an effect that concert had on me.  "I just remember that moment: Here's that full-on rock section, with Kenny Aronoff on drums and Larry Crane a rock guitarist with swagger. But there was also Lisa Germano on fiddle, they had an accordion player, there was an acoustic guitarist. I was hit by lightning by that concert. I said to John, 'I didn't walk away thinking: I want to do that. I walked away feeling: I get it -- just put all the things you love into what you do.' It was singularly the most important concert I've ever been to in my life because it showed me the way."  Urban went into more detail on the impact Mellencamp's Lonesome Jubilee Tour concert had on him when CMT asked him about the concert that most influenced him: "The most impactful one for me was probably John Mellencamp in '88 or '89 on the Lonesome Jubilee Tour. It was singularly the most epiphany experience I'd ever had at a concert. Prior to that, from the age of 6 or 7, I was somewhere in between Top 40, country and, 'Who the hell am I and what do I do?' But The Lonesome Jubilee came out. I loved 'Paper in Fire' and 'Check It Out' because it was such a melting pot of things. But when I went to see him live, his band was so phenomenally good. Great, great band. And I remember watching the concert - and the light went off. There's a rock rhythm section, but there's acoustic guitar, electric guitar. This fiddle, this accordion. He's singing these rural lyrics, but he's got swagger and attitude for days. It was like everything came together. I got to talk to John years later, and I said to him how much that concert changed my life. I didn't leave that concert thinking 'I want to be Mellencamp.' I went away going, 'Take all of your influences and make your own thing.' It was such a liberating experience for me."  Urban has covered numerous Mellencamp songs in his concerts over the years, including "Hurts So Good", "Jack and Diane", "Authority Song", and "Rumbleseat". In 2015, Urban and Mellencamp performed "Pink Houses" together twice during nationally televised events. Urban's 2015 hit single "John Cougar, John Deere, John 3:16" further illustrated Mellencamp's influence on his music.
Why was it defining
A:
it was one of the greatest opportunities I've ever had to meet a hero and tell him about a concert you went to when you were a nobody